staging: gasket: page table: use dma_mapping_error for error detection

gasket_perform_mapping() call dma_mapping_error() to determine if
mapping failed.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed