Add parentheses to avoid warning

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@58877 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/gis/mkstemp.c

@@ -161,7 +161,7 @@ int G_mkstemp(char *template, int flags, int mode)
 
 FILE *G_mkstemp_fp(char *template, int flags, int mode)
 {
-    const char *fmode = (flags & O_ACCMODE == O_RDWR)
+    const char *fmode = ((flags & O_ACCMODE) == O_RDWR)
 	? ((flags & O_APPEND) ? "a+" : "w+")
 	: ((flags & O_APPEND) ? "a" : "w");
     int fd = G_mkstemp(template, flags, mode);