compiler-rt: Support thumb versions older than armv6

Add versions of __aeabi_memset and __aeabi_memclr which do not use mov
instructions between low registers, as this is unsupported on thumbv4t
and thumbv5.
cd02630da8Carter Sande committed on 6/25/2019, 5:32:50 AMparentde2b0cd
1 file changedLine totals unavailable