drivers/rtc/rtc-ds1742.c: revert "drivers/rtc/rtc-ds1742.c: remove redundant of_match_ptr() helper"

Commit 5516f097 ("drivers/rtc/rtc-ds1742.c: remove redundant
of_match_ptr() helper") has description as: "'ds1742_rtc_of_match' is
always compiled in.  Hence the helper macro is not needed".

It is not true, of_match_ptr() macro makes of_device_id parameter unused
and this constant is declared with __maybe_unused attribute, so normally
this variable should be discarded by linker.  This patch revers this
commit, since there are no reason to compile of_device_id constant for
non-DT systems.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>