This patch is to make current ARM target triplet matching more general
to handle some target triplets like armv7l-linux-gnueabi and
armv6l-linux-gnueabi.

Some of test cases have been changed to arm*-*-* or arm*-*eabi*.  So
this patch helps to make whole testsuite in a consistent state.

OK to apply to mainline and 7.2 branch?

-- 
Yao (齐尧)