Mark armv6m as "compatible" with armv7 - that's the
closest ISA.  armv6 wouldn't have the handful of
T32 instructions that the Cortex-M0 ISA specifies.
<rdar://problem/15099306> 


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@191588 91177308-0d34-0410-b5e6-96231b3b80d8