Turned CPU detection into a function

libretro-config.sh

@@ -2,6 +2,8 @@
 # vi: ts=3 sw=3 et
 
 # Architecture Assignment
+config_cpu() {
+   [ -n "${2}" ] && ARCH=${1}
    [ -z "${ARCH}" ] && ARCH="`uname -m`"
    case "${ARCH}" in
       x86_64)
@@ -26,6 +28,9 @@ if [ -n "${PROCESSOR_ARCHITEW6432}" -a "${PROCESSOR_ARCHITEW6432}" = "AMD64" ];
       ARCH=x86_64
       X86=true && X86_64=true
    fi
+}
+
+config_cpu
 
 if [ -z "$JOBS" ]; then
    if command -v nproc >/dev/null; then