staging: gasket: page table: hold references to device and pci_dev

Hold references to the struct device and the pci_dev for the page table
while the data structures contian pointers to these.
Signed-off-by: NTodd Poynor <toddpoynor@google.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gasket/gasket_page_table.c

@@ -345,8 +345,8 @@ int gasket_page_table_init(
 		bar_data->virt_base[page_table_config->base_reg]);
 	pg_tbl->extended_offset_reg = (u64 __iomem *)&(
 		bar_data->virt_base[page_table_config->extended_reg]);
-	pg_tbl->device = device;
-	pg_tbl->pci_dev = pci_dev;
+	pg_tbl->device = get_device(device);
+	pg_tbl->pci_dev = pci_dev_get(pci_dev);
 
 	dev_dbg(device, "Page table initialized successfully\n");
 
@@ -364,6 +364,8 @@ void gasket_page_table_cleanup(struct gasket_page_table *pg_tbl)
 	vfree(pg_tbl->entries);
 	pg_tbl->entries = NULL;
 
+	put_device(pg_tbl->device);
+	pci_dev_put(pg_tbl->pci_dev);
 	kfree(pg_tbl);
 }