rtc: s5m: De-inline large functions to save space

Few functions were marked inline even though they were relatively large
and sometimes used in multiple places. De-inline them to let the
compiler decide whether optimization makes sense. This fixes inline_hunt
report:
drivers/rtc/rtc-s5m.c: Deinline s5m8767_rtc_set_alarm_reg, save 704 bytes
drivers/rtc/rtc-s5m.c: Deinline s5m8767_wait_for_udr_update, save 192 bytes

Reported-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>