asm/mce.h is not available on arm, and it is not needed to build nfit.c.
Remove the include.

It was likely needed for COPY_MC_TEST

Fixes: 3adb7763 ("x86, libnvdimm/test: Remove COPY_MC_TEST")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Link: https://lore.kernel.org/r/20220429074334.21771-1-msuchanek@suse.deSigned-off-by: Dan Williams <dan.j.williams@intel.com>