Add missing backslash in MIPS filelist

Change-Id: I993ea7038cd641ea167d974226e2350e49d41c88
diff --git a/libc/Android.mk b/libc/Android.mk
index 4f8debd..f3a4dcf 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -488,7 +488,7 @@
 	string/strncmp.c \
 	string/strncpy.c \
 	string/strrchr.c \
-	upstream-freebsd/lib/libc/string/wcscat.c
+	upstream-freebsd/lib/libc/string/wcscat.c \
 	upstream-freebsd/lib/libc/string/wcschr.c \
 	upstream-freebsd/lib/libc/string/wcscmp.c \
 	upstream-freebsd/lib/libc/string/wcscpy.c \