builtins: replace section symbol with reference to spec

Removes a non-ascii character that was committed.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@217353 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit edd11e1dc56d8e4e619cbbe7d745960bf8aeeae4)
1 file changed