push LOAD_ADDR out to arch mk files

Rather than maintain/extend the current ifeq($(ARCH)) mess that exists in
the standalone Makefile, push the setting up of LOAD_ADDR out to the arch
config.mk (and rename to STANDALONE_LOAD_ADDR in the process).  This keeps
the common code clean and lets the arch do whatever crazy crap it wants in
its own area.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/lib_sparc/config.mk b/lib_sparc/config.mk
index 07b528c..4de6515 100644
--- a/lib_sparc/config.mk
+++ b/lib_sparc/config.mk
@@ -23,4 +23,6 @@
 
 CROSS_COMPILE ?= sparc-elf-
 
+STANDALONE_LOAD_ADDR = 0x00000000 -L $(gcclibdir) -T sparc.lds
+
 PLATFORM_CPPFLAGS += -DCONFIG_SPARC -D__sparc__