rtc: Update interface.c to use y2038-safe time interfaces
rtc: Update interface.c to use y2038-safe time interfaces

Currently, interface.c uses y2038 problematic rtc_tm_to_time()
and rtc_time_to_tm(). So replace them with their corresponding
y2038-safe versions: rtc_tm_to_time64() and rtc_time64_to_tm().

Cc: pang.xunlei <8f3df7547938bf466547d5e4573831d5224028fc@linaro.org>
Cc: Arnd Bergmann <31ce0e01d6a887319e98c2278af71350d5f64c4f@linaro.org>
Cc: Thomas Gleixner <00e4cf8f46a57000a44449bf9dd8cbbcc209fd2a@linutronix.de>
Cc: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@kernel.org>
Signed-off-by: Xunlei Pang <8f3df7547938bf466547d5e4573831d5224028fc@linaro.org>
Signed-off-by: John Stultz <33837adfb53316eae44aad04041e1240088d76fd@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs