log10: Use sw implementation from amd builtins

Add missing table.
Fixes log10d CTS on carrizo.
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Acked-by: Aaron Watry <awatry@gmail.com>
Tested-by: Aaron Watry <awatry@gmail.com>

llvm-svn: 330649