MinGW compile error with rev 10888

[Li-Hui Zhou]

I appriciate your work on compiling problems with MinGW. But the latest
rev 11041 still gives another kind of error messages:

compat.c: In function `tor_addr_lookup':
compat.c:1131: error: incompatible type for argument 1 of `memcpy'
compat.c:1133: error: structure has no member named `sin6_addr'
compat.c:1136: error: syntax error before '}' token
make[3]: *** [compat.o] Error 1