* sparc.c: Use __asm__ instead of asm for gcc.
  gcc doesn't provide asm keyword if -ansi option is given.
  http://gcc.gnu.org/onlinedocs/gcc/Alternate-Keywords.html


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40496 b2dd03c8-39d4-4d8f-98ff-823fe69b080e