build: Drop libgcc runtime wrapper in Clang builds

This GCC specific workaround of wrapping of libgcc runtime symbols with
gcc.c is not nessary with libcompiler-rt linkage.

Change-Id: I50a2bc99d97f68a2ad2b51a92ea0e7086bab35fe
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5812
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
diff --git a/src/lib/Makefile.inc b/src/lib/Makefile.inc
index f82a3fa..522f43a 100644
--- a/src/lib/Makefile.inc
+++ b/src/lib/Makefile.inc
@@ -36,7 +36,10 @@
 endif
 
 romstage-y += compute_ip_checksum.c
+ifneq ($(CONFIG_COMPILER_LLVM_CLANG),y)
 romstage-$(CONFIG_ARCH_ROMSTAGE_X86_32) += gcc.c
+ramstage-$(CONFIG_ARCH_RAMSTAGE_X86_32) += gcc.c
+endif
 
 ramstage-y += hardwaremain.c
 ramstage-y += selfboot.c
@@ -54,7 +57,6 @@
 ramstage-y += lzma.c
 #ramstage-y += lzmadecode.c
 ramstage-y += stack.c
-ramstage-$(CONFIG_ARCH_RAMSTAGE_X86_32) += gcc.c
 ramstage-y += clog2.c
 romstage-y += clog2.c
 ramstage-$(CONFIG_CONSOLE_CBMEM) += cbmem_console.c