mozjs60: use generic libatomic checks

srcpkgs/mozjs60/template

@@ -17,9 +17,10 @@ patch_args="-Np1"
 CXXFLAGS="-Wno-class-memaccess"
 LDFLAGS+=" -Wl,-z,stack-size=1048576"
 
-case "$XBPS_TARGET_MACHINE" in
-	armv[56]*|mips*|ppc|ppc-musl) makedepends+=" libatomic-devel" ; LDFLAGS+=" -latomic" ;;
-esac
+if [ "$XBPS_TARGET_NO_ATOMIC8" ]; then
+	makedepends+=" libatomic-devel"
+	LDFLAGS+=" -latomic"
+fi
 
 do_configure() {
 	local _args