rtc: pcf2127: cleanup register and bit defines

rtc: pcf2127: cleanup register and bit defines

Cleanup of defines to follow kernel coding style and increase code
readability by using same register and bit define style.

Change PCF2127_REG_RAM_{addr_MSB,wrt_cmd,rd_cmd} to upper case as
kernel coding guide section 12 'Macros, Enums and RTL' states
"Names of macros defining constants and labels in enums are capitalized".

Improve readability of RAM register comment by making whole sentences.

Remove parentheses from register defines as they are only used
for expressions and not constants.

As there are no clear style for name of registers and bits in the
kernel drivers, I suggest the following for at least this driver,
but hopefully also other RTC drivers.

Register name should follow this convention:
[chip]_REG_[reg name] 0xXX

Bit name should follow this convention, so it clearly states which
chip register it's part of:
[chip]_BIT_[reg name]_[bit name] BIT(X)

Additionally I suggest bit defines are always placed right below
its corresponding register define and using an extra tab indentation
for the BIT(X) part. This will visually make it easy to see that bit
defines are part of the complete register definition.

Rename PCF2127_OSF to PCF2127_BIT_SC_OSF and move it right below
PCF2127_REG_SC. This will improve readability of bit checks as it's
easy to verify that it uses the correct register.

Move end of line comments above register defines as it's more like
a heading for 1 register define and up to 8 bit defines or a
collection of registers that are close related like timestamp
split across 6 registers.

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-2-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>