Win32: fixed some warnings reported by Borland C. Most notably, warning W8012 (comparing signed and unsigned values) reported in multiple places where an unsigned value of small type (e.g., u_short) is promoted to an int and compared to an unsigned value. Warning W8072 (suspicious pointer arithmetic) disabled, it is reported when we increment base pointer in ngx_shm_alloc().

--- a/src/os/win32/ngx_win32_config.h
+++ b/src/os/win32/ngx_win32_config.h
@@ -119,6 +119,9 @@ typedef long  time_t;
 /* unreferenced formal parameter */
 #pragma warn -8057
 
+/* suspicious pointer arithmetic */
+#pragma warn -8072
+
 #endif