Since commit 6d0ae9e19d98 ("Documentation: update for gcc 4.9
requirement") the minimum supported version of GCC is gcc-4.9. It's now
safe to remove this code.
Similar to commit b679f7e03712 ("gcov: Remove old GCC 3.4 support") but
that was for GCC 4.8 and this is for GCC 4.9.