mk: fix extra options when linking lib through compiler

When using a linker option not known by the compiler like -rpath,
the library linkage was failing.
It is fixed by prefixing the option with -Wl, as it is done in other
makefiles.

Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

mk/rte.lib.mk

@@ -68,6 +68,7 @@ ifeq ($(LINK_USING_CC),1)
 # Override the definition of LD here, since we're linking with CC
 LD := $(CC) $(CPU_CFLAGS)
 _CPU_LDFLAGS := $(call linkerprefix,$(CPU_LDFLAGS))
+override EXTRA_LDFLAGS := $(call linkerprefix,$(EXTRA_LDFLAGS))
 else
 _CPU_LDFLAGS := $(CPU_LDFLAGS)
 endif