tpm2-abrmd: allow building without stack smashing protection (SSP)

tpm2-abrmd: allow building without stack smashing protection (SSP)

Disable SSP if the toolchain does not support it. This must be done
explicitly because configure.ac passes -fstack-protector-all to the
compiler but doesn't contain a link test, so it doesn't detect when
libssp is missing.

Fixes:
  http://autobuild.buildroot.net/results/83ad1f33f523321f841e70d2d8cf5ce861dee217
  http://autobuild.buildroot.net/results/cef047751534fef23d1022e9a276424bc84bf461
  http://autobuild.buildroot.net/results/6048355337804f7841dffa1655f44b9f6db56314
  http://autobuild.buildroot.net/results/d934a2ea90e7bf1c7b93dbb367998abab536daf4
  http://autobuild.buildroot.net/results/c0daaf37b8d1515d62d2441ba6aa57125437e191
  http://autobuild.buildroot.net/results/9482ea5554938865e0061dcbdcf3c2c918b96954
  http://autobuild.buildroot.net/results/282a8b6769f19f0a40089207bc54e7302663751f

Signed-off-by: Carlos Santos <casantos@datacom.ind.br>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>