regmap: Allow longer flag masks for read and write

We currently only support masking the top bit for read and write
flags. Let's make the mask unsigned long and mask the bytes based
on the configured register length to make things more generic.

This allows using regmap for more exotic combinations like SPI
devices that need little endian addressing.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index a038033..6636f03 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -105,8 +105,8 @@
 
 	bool defer_caching;
 
-	u8 read_flag_mask;
-	u8 write_flag_mask;
+	unsigned long read_flag_mask;
+	unsigned long write_flag_mask;
 
 	/* number of bits to (left) shift the reg value when formatting*/
 	int reg_shift;