Fix two bugs for musl-libc on ARM
Bug 1: triples like armv7-pc-linux-musl use the wrong linker name
ld-musl-armv7.so.1; the right name should be ld-musl-arm.so.1, disregarding the
subarch field.
Bug 2: when compiler option -mhard-float is used, we should use the "hardfloat"
linker, no matter whether the triple itself mentions "hardfloat".
Patch by Lei Zhang!
Differential Revision: https://reviews.llvm.org/D22904
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@277985
91177308-0d34-0410-b5e6-
96231b3b80d8