ldns: fix building with GCC 12

parse.c performs pointer arithmetic with a pointer to a memory area
that's been reallocated in the meantime. It is very inelegant but looks
harmless otherwise.

This change sets the -Wno-use-after-free flag with GCC for this file.

lib/libldns/Makefile

@@ -23,6 +23,7 @@ LIBADD=	ssl crypto
 
 WARNS ?= 3
 
+CWARNFLAGS.parse.c=	${NO_WUSE_AFTER_FREE}
 CWARNFLAGS.sha2.c=	${NO_WARRAY_PARAMETER}
 
 .include <bsd.lib.mk>