bus: mhi: Cleanup the register definitions used in headers

Cleanup includes:

1. Using the GENMASK macro for masks
2. Removing brackets for single values
3. Using lowercase for hex values
4. Using two digits for hex values where applicable
5. Aligning the defines on same column
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-8-manivannan.sadhasivam@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>