libclamav: Define HAVE_CLI_GETPAGESIZE for Windows builds

This makes the blob allocator behave the same on Windows and on
Linux by defaulting to memory allocations in units of the page size
instead of performing the allocations all at once (for better or
worse; it's unclear which is better on modern systems that are
already expected to have > 1 GB of memory to load the official
signature sets).

libclamav/others.h

@@ -759,6 +759,7 @@ static inline int cli_getpagesize(void)
     GetSystemInfo(&si);
     return si.dwPageSize;
 }
+#define HAVE_CLI_GETPAGESIZE 1
 #else /* ! _WIN32 */
 #if HAVE_SYSCONF_SC_PAGESIZE
 static inline int cli_getpagesize(void)