rtc: add missing MODULE_DESCRIPTION() macro

rtc: add missing MODULE_DESCRIPTION() macro

On x86, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/lib_test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-goldfish.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-omap.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-rc5t583.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-tps65910.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-twl.o

Add the missing invocation of the MODULE_DESCRIPTION() macro to all
files which have a MODULE_LICENSE(). This includes rtc-mpc5121.c,
which does not produce a warning with the x86 allmodconfig since it is
not built for x86, but it may cause this warning with Freescale PPC
configurations.

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240608-md-drivers-rtc-v1-1-5f44222adfae@quicinc.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>