Change some inline assembler so it is no longer rejected by clang
as suggested by John Reiser and Greg Parker.
It seems that GCC has a more relaxed attitude about what it accepts
as valid input.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13610 a5019735-40e9-0310-863c-91ae7b9d1cf9