s390/hwcaps: remove hwcap stfle check

Remove the not so obvious "(elf_hwcap & (1UL << 2)" which only checks
if stfle is available. This used to be required for old code before
test_facility() was introduced. test_facility() will do the right
thing, regardless if stfle is available or not.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>