xenbus_client.c: correct exit path for xenbus_map_ring_valloc_hvm
xenbus_client.c: correct exit path for xenbus_map_ring_valloc_hvm

Apparently we should not free page that has not been allocated.
This is b/c alloc_xenballooned_pages will take care of freeing
the page on its own.

Signed-off-by: Wei Liu <a5240e9e4c4d742e3a4232ca749f78defd45d722@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <da3a51b335cef0eb0e2c329c5ef6bcd6acef687a@oracle.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs