builtins: repair __gtsf2 after SVN r291396
The argument adjustment was accidentally removed, resulting in the use
of stale register values.
@@ -215,6 +215,8 @@ LOCAL_LABEL(CHECK_NAN_2):
6:
pop {r6, pc}
#else
+ mov r2, r0, lsl #1
+ mov r3, r1, lsl #1
orrs r12, r2, r3, lsr #1
it ne
eorsne r12, r0, r1
