platform/mellanox: mlxreg-io: Fix read access of n-bytes size attributes

Fix shift argument for function rol32(). It should be provided in bits,
while was provided in bytes.

Fixes: 86148190a7db ("platform/mellanox: mlxreg-io: Add support for complex attributes")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20210927142214.2613929-3-vadimp@nvidia.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/drivers/platform/mellanox/mlxreg-io.c b/drivers/platform/mellanox/mlxreg-io.c
index a023ec0..a916cd8 100644
--- a/drivers/platform/mellanox/mlxreg-io.c
+++ b/drivers/platform/mellanox/mlxreg-io.c
@@ -98,7 +98,7 @@
 			if (ret)
 				goto access_error;
 
-			*regval |= rol32(val, regsize * i);
+			*regval |= rol32(val, regsize * i * 8);
 		}
 	}