Disable MBEDTLS_HAVE_DATE_TIME as ARMCC does not support gmtime

[andresag01]

Description

This PR reverts the change #4846 which enabled the feature MBEDTLS_HAVE_DATE_TIME in Mbed TLS as the libc used by the ARM toolchain does not fully implement the gmtime() function that this feature relies on.

Pull request type

[X] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Breaking change

[andresag01]

cc @sbutcher-arm

[simonbutcher]

Maintainers - can you please add @k-stachowiak and @AndrzejKurek as reviewers?

@k-stachowiak - Can you please test this PR on a board and append to this PR what test you did when you have?

[k-stachowiak]

I built (with ARM and GCC_ARM compilers) and ran (on a K64F board) all the mbed-os-example-tls examples (master branch) updated with mbed-os.lib pointing to: "[email protected]:andresag01/mbed/#d7519565d22249fa2c0f2ec4c60a2c0e3981b916", which is the last commit in this PR.
All the examples ran fine except for the benchmark application, which reported an error after the run (log below). I don't think the error is related to this PR, therefore I don't see a reason not to approve it.

  SHA-256                  :       2073 KB/s
  SHA-512                  :        812 KB/s
  AES-CBC-128              :        882 KB/s
  AES-CBC-192              :        754 KB/s
  AES-CBC-256              :        658 KB/s
  AES-GCM-128              :        509 KB/s
  AES-GCM-192              :        463 KB/s
  AES-GCM-256              :        424 KB/s
  AES-CCM-128              :        399 KB/s
  AES-CCM-192              :        345 KB/s
  AES-CCM-256              :        304 KB/s
  AES-CMAC-128             :        783 KB/s
  AES-CMAC-192             :        679 KB/s
  AES-CMAC-256             :        598 KB/s
  AES-CMAC-PRF-128         :        782 KB/s
  CTR_DRBG (NOPR)          :        629 KB/s
  CTR_DRBG (PR)            :        468 KB/s
  HMAC_DRBG SHA-256 (NOPR) :        229 KB/s
  HMAC_DRBG SHA-256 (PR)   :        202 KB/s
  RSA-2048                 :      40 ms/ public
  RSA-2048                 :    1545 ms/private
  RSA-4096                 :     138 ms/ public
  RSA-4096                 :    8775 ms/private
  ECDSA-secp384r1          :     492 ms/sign
  ECDSA-secp256r1          :     303 ms/sign
  ECDSA-secp384r1          :     918 ms/verify
  ECDSA-secp256r1          :     594 ms/verify
  ECDHE-secp384r1          :     881 ms/handshake
  ECDHE-secp256r1          :     562 ms/handshake
  ECDHE-Curve25519         :     525 ms/handshake
  ECDH-secp384r1           :     430 ms/handshake
  ECDH-secp256r1           :     278 ms/handshake
  ECDH-Curve25519          :     268 ms/handshake

DONE


++ MbedOS Error Info ++
                       Error Status: 0x80020125 Code: 293 Module: 2
                                                                   Error Message: CMSIS-RTOS error: Stack overflow
                                                                                                                  Location: 0x1743B
                                                                                                                                   Error Value: 0x1
         Current Thread: Id: 0x200022A8 Entry: 0x187D5 StackSize: 0x1000 StackMem: 0x200012A8 SP: 0x2002FF88
                                                                                                             -- MbedOS Error Info --

[0xc0170]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 2938
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/7868/

Triggering tests

/morph test
/morph export-build
/morph mbed2-build

[mbed-ci]

Exporter Build : SUCCESS

Build number : 2557
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7868/

[mbed-ci]

Test : SUCCESS

Build number : 2688
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/7868/2688

[cmonr]

I would have prefered this somehow be an ARM-only change, but this is fine as well since it simplifies maintenance overhead.