lib/Makefile.inc: Stop gcc.c getting into SMM clang builds

The libgcc runtime workarounds found in gcc.c are not needed for
compiler-rt used by the Clang toolchain. Stop gcc.c from sneaking into
Clang builds while processing boards that use SMM code.

Change-Id: I51e8d517784721d28b4d951bd0bebc8b52682a8e
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/6121
Tested-by: build bot (Jenkins)
Reviewed-by: Idwer Vollering <vidwer@gmail.com>
build: Pass correct disassembly flags in Clang build

On SVR4-derived platforms, the character `/' is treated as a comment
character, which means that it cannot be used in expressions. The
`--divide' option turns `/' into a normal character. This seems to be
needed with our local build of binutils since we don't yet use the
internal assembler/disassembler of the Clang tooling.

Change-Id: I344fc8670fd5d994f3b63308a513dd367aefc7f9
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5813
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>