android_getaddrinfo_proxy: fix memory leak on failure.

The shadowing of `ai` meant that the freeaddrinfo() call outside the
loop would never see anything but NULL.

Bug: https://issuetracker.google.com/143928781
Test: treehugger
Change-Id: I1bf137f7933201eb8024603bfd569ff7bbc7f9b7
diff --git a/libc/dns/net/getaddrinfo.c b/libc/dns/net/getaddrinfo.c
index 4e1aa61..d0c11d2 100644
--- a/libc/dns/net/getaddrinfo.c
+++ b/libc/dns/net/getaddrinfo.c
@@ -470,7 +470,7 @@
 			break;
 		}
 
-		struct addrinfo* ai = calloc(1, sizeof(struct addrinfo) + sizeof(struct sockaddr_storage));
+		ai = calloc(1, sizeof(struct addrinfo) + sizeof(struct sockaddr_storage));
 		if (ai == NULL) {
 			break;
 		}