rtc: i2c/spi: Avoid inclusion of REGMAP support when not needed

rtc: i2c/spi: Avoid inclusion of REGMAP support when not needed

Merely enabling I2C and RTC selects REGMAP_I2C and REGMAP_SPI, even when
no driver needs it.  While the former can be moduler, the latter cannot,
and thus becomes built-in.

Fix this by moving the select statements for REGMAP_I2C and REGMAP_SPI
from the RTC_I2C_AND_SPI helper to the individual drivers that depend on
it.

Note that the comment for RTC_I2C_AND_SPI refers to SND_SOC_I2C_AND_SPI
for more information, but the latter does not select REGMAP_{I2C,SPI}
itself, and defers that to the individual drivers, too.

Fixes: 080481f54ef62121 ("rtc: merge ds3232 and ds3234")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20200112171349.22268-1-geert@linux-m68k.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>