ms_block: fix spelling mistake "doesn'" -> "doesn't"

There is a spelling mistake in a debug message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200810080247.47024-1-colin.king@canonical.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/memstick/core/ms_block.c

@@ -1223,7 +1223,7 @@ static int msb_read_boot_blocks(struct msb_data *msb)
 		}
 
 		if (be16_to_cpu(page->header.block_id) != MS_BLOCK_BOOT_ID) {
-			dbg("the pba at %d doesn' contain boot block ID", pba);
+			dbg("the pba at %d doesn't contain boot block ID", pba);
 			continue;
 		}