Merge "configure: enable -Wunused-function by default"

configure

diff --git a/configure b/configure
index 5fbd2d0..095cddf 100755
--- a/configure
+++ b/configure
@@ -600,7 +600,11 @@
           ;;
           *) check_add_cflags -Wunused-but-set-variable ;;
         esac
-        enabled extra_warnings || check_add_cflags -Wno-unused-function
+        if enabled mips || [ -z "${INLINE}" ]; then
+          enabled extra_warnings || check_add_cflags -Wno-unused-function
+        else
+          check_add_cflags -Wunused-function
+        fi
     fi
 
     if enabled icc; then