Use gcc-ar and gcc-ranlib wrappers

These wrappers use the --plugin flags to properly support LTO, other
than that it's a transparent change.

src/base/build.mak

@@ -18,8 +18,8 @@ CC       = psp-gcc
 CXX      = psp-g++
 AS       = psp-gcc
 LD       = psp-gcc
-AR       = psp-ar
-RANLIB   = psp-ranlib
+AR       = psp-gcc-ar
+RANLIB   = psp-gcc-ranlib
 STRIP    = psp-strip
 MKSFO    = mksfo
 PACK_PBP = pack-pbp