Add test for ARMv6-M farcall with no profile info

2015-12-24  Thomas Preud'homme  <thomas.preudhomme@arm.com>

ld/testsuite/
    * ld-arm/arm-elf.exp: Run new test "Thumb-Thumb farcall v6-M (no
    profile)".
    * ld-arm/farcall-thumb-thumb-m-no-profile-a.s: New file.
    * ld-arm/farcall-thumb-thumb-m-no-profile-b.s: Likewise.
    * ld-arm/farcall-thumb-thumb-m-no-profile.d: Likewise.