[2.4.2-only] GCC: Fix uu_ident.c strchr()

Convert 'char *' to 'const char *' to make GCC happy on Fedora 44.

Signed-off-by: Tony Hutter <hutter2@llnl.gov>

lib/libuutil/uu_ident.c

@@ -76,7 +76,7 @@ is_valid_ident(const char *s, const char *e, int allowdot)
 static int
 is_valid_component(const char *b, const char *e, uint_t flags)
 {
-	char *sp;
+	const char *sp;
 
 	if (flags & UU_NAME_DOMAIN) {
 		sp = strchr(b, ',');