This reverts commit e0d8b2ec.

For at least GCC 4.8.3, adding nomips16 function attribute still cannot
prevent it from being inlined in mips16 context.  So revert it first in
preparation for a better workaround.

 [1] Inlining nomips16 function into mips16 function can result in
     undefined builtins, https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55777Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11240/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>