ANDROID: GKI: fix build breakage in io_uring during 6.1.132 merge

In commit 9aeb6833 ("io_uring: get rid of remap_pfn_range() for
mapping rings/sqes"), direct access to vm_flags was attempted, but
that's not allowed anymore in the Android 6.1 branch due to other
upstream changes merged into here.  Fix this up by calling the proper
vm_flags_set() function instead.

Fixes: 9aeb6833 ("io_uring: get rid of remap_pfn_range() for mapping rings/sqes")
Change-Id: I05bdf96a2f6760e9388237d71d2471c373e29c0c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>