Feat(read_lib): Gz lib format support

[wjrforcyber]

Why this

According to some issues in thread: YosysHQ/yosys#4830 and YosysHQ/yosys#4830 (comment)
.gz format is needed.

How this is added

1. I notice that read_aiger and read_blif support .gz format, I use the same function interface here and rename it as Io_LibLoadFileGz.
2. As for p->nContents, I change it to a pointer, it will be updated by the gz interface, and it will remain the same in normal .lib format.

Test & verify

• I use the Nangate45 lib file, gzip it and read it in abc to check the content of p->pContents, it can be verified to be the same.
• Same output.

./abc -c "read_lib NangateOpenCellLibrary_typical.lib"
ABC command line: "read_lib NangateOpenCellLibrary_typical.lib".

Library "NangateOpenCellLibrary" from "NangateOpenCellLibrary_typical.lib" has 90 cells (35 skipped: 21 seq; 6 tri-state; 8 no func; 10 dont_use).  Time =     0.05 sec
Warning: Detected 2 multi-output gates (for example, "FA_X1").

./abc -c "read_lib NangateOpenCellLibrary_typical.lib.gz"
ABC command line: "read_lib NangateOpenCellLibrary_typical.lib.gz".

Library "NangateOpenCellLibrary" from "NangateOpenCellLibrary_typical.lib.gz" has 90 cells (35 skipped: 21 seq; 6 tri-state; 8 no func; 10 dont_use).  Time =     0.06 sec
Warning: Detected 2 multi-output gates (for example, "FA_X1").

• No leaks.

leaks --atExit -- ./abc -c "read_lib NangateOpenCellLibrary_typical.lib"   
abc(34863) MallocStackLogging: could not tag MSL-related memory as no_footprint, so those pages will be included in process footprint - (null)
abc(34863) MallocStackLogging: recording malloc and VM allocation stacks using lite mode
ABC command line: "read_lib NangateOpenCellLibrary_typical.lib".

Library "NangateOpenCellLibrary" from "NangateOpenCellLibrary_typical.lib" has 90 cells (35 skipped: 21 seq; 6 tri-state; 8 no func; 10 dont_use).  Time =     0.05 sec
Warning: Detected 2 multi-output gates (for example, "FA_X1").
Process 34863 is not debuggable. Due to security restrictions, leaks can only show or save contents of readonly memory of restricted processes.

Process:         abc [34863]
Path:            /Users/USER/*/abc
Load Address:    0x1043d4000
Identifier:      abc
Version:         0
Code Type:       ARM64
Platform:        macOS
Parent Process:  leaks [34862]

Date/Time:       2025-01-21 16:07:16.812 +0800
Launch Time:     2025-01-21 16:07:16.555 +0800
OS Version:      macOS 14.6 (23G80)
Report Version:  7
Analysis Tool:   /usr/bin/leaks

Physical footprint:         8785K
Physical footprint (peak):  17.8M
Idle exit:                  untracked
----

leaks Report Version: 4.0, multi-line stacks
Process 34863: 189 nodes malloced for 15 KB
Process 34863: 0 leaks for 0 total leaked bytes.

leaks --atExit -- ./abc -c "read_lib NangateOpenCellLibrary_typical.lib.gz"
abc(35732) MallocStackLogging: could not tag MSL-related memory as no_footprint, so those pages will be included in process footprint - (null)
abc(35732) MallocStackLogging: recording malloc and VM allocation stacks using lite mode
ABC command line: "read_lib NangateOpenCellLibrary_typical.lib.gz".

Library "NangateOpenCellLibrary" from "NangateOpenCellLibrary_typical.lib.gz" has 90 cells (35 skipped: 21 seq; 6 tri-state; 8 no func; 10 dont_use).  Time =     0.07 sec
Warning: Detected 2 multi-output gates (for example, "FA_X1").
Process 35732 is not debuggable. Due to security restrictions, leaks can only show or save contents of readonly memory of restricted processes.

Process:         abc [35732]
Path:            /Users/USER/*/abc
Load Address:    0x102b38000
Identifier:      abc
Version:         0
Code Type:       ARM64
Platform:        macOS
Parent Process:  leaks [35731]

Date/Time:       2025-01-21 16:07:27.548 +0800
Launch Time:     2025-01-21 16:07:27.313 +0800
OS Version:      macOS 14.6 (23G80)
Report Version:  7
Analysis Tool:   /usr/bin/leaks

Physical footprint:         10.8M
Physical footprint (peak):  18.6M
Idle exit:                  untracked
----

leaks Report Version: 4.0, multi-line stacks
Process 35732: 189 nodes malloced for 15 KB
Process 35732: 0 leaks for 0 total leaked bytes.