tests,base: Added GTests for exec_ecoff.h and exec_aout.h

Change-Id: Iec76ba24a06425caefd28d640c6479720f401c06
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22323
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>
4 files changed