Revert "Check malloc return"

This reverts commit 6da0cfda.

That was a stupid commit, the malloc failure is already handled

Spotted by: @scn

lib/libvarnish/vcli_proto.c

@@ -168,7 +168,6 @@ VCLI_ReadResult(int fd, unsigned *status, char **ptr, double tmo)
 
 		*status = u;
 		p = malloc(v + 1L);
-		AN(p);
 		if (p == NULL)
 			break;