basic: add STRCASE_IN_SET() which is to STR_IN_SET() what strcaseeq() is to streq()

src/basic/strv.c

@@ -28,6 +28,18 @@ char *strv_find(char * const *l, const char *name) {
         return NULL;
 }
 
+char *strv_find_case(char * const *l, const char *name) {
+        char * const *i;
+
+        assert(name);
+
+        STRV_FOREACH(i, l)
+                if (strcaseeq(*i, name))
+                        return *i;
+
+        return NULL;
+}
+
 char *strv_find_prefix(char * const *l, const char *name) {
         char * const *i;