Export the given symbols list

[waruqi]

Support macosx (.dylib), windows (.dll), linux (.so). It will use *.def, version scripts .map/.ver and -export_symbols_list to export them automatically.

We can use it to reduce the size of the dynamic library and export only the symbols we need.

project example: https://github.com/xmake-io/xmake/tree/dev/tests/projects/c/shared_library_export_list

Export the given symbols list in xmake.lua

target("foo")
    set_kind("shared")
    add_files("src/foo.c")
    add_rules("utils.symbols.export_list", {symbols = {
        "add",
        "sub"}})

Export the given symbols list in *.export.txt file

target("foo2")
    set_kind("shared")
    add_files("src/foo.c")
    add_files("src/foo.export.txt")
    add_rules("utils.symbols.export_list")

Export all symbols

#1123 (comment)