The ppc4xx support breaks with our toolchain and we don't want it anyway.

--- a/configure
+++ b/configure
@@ -5939,7 +5939,7 @@ elif enabled ppc; then
 
     check_inline_asm dcbzl     '"dcbzl 0, %0" :: "r"(0)'
     check_inline_asm ibm_asm   '"add 0, 0, 0"'
-    check_inline_asm ppc4xx    '"maclhw r10, r11, r12"'
+    disable ppc4xx
     check_inline_asm xform_asm '"lwzx %1, %y0" :: "Z"(*(int*)0), "r"(0)'
 
     if enabled altivec; then