Fix Alpine 3.13 ARM build (#50105)

Fix Alpine 3.13 ARM build (#50105)

* Fix Alpine 3.13 ARM build

Alpine 3.13 is the first version of Alpine Linux that uses 64 bit time_t
on both 64 and 32 bit platforms. That breaks the build as we assumed
that 32 bit platforms use always 32 bit time_t.

This change fixes it by making the PAL time_t type always 64 bit.
Everything still works fine on non-Alpine ARM / x86 Linuxes, since
it only changes the time_t type size outside of PAL.

* Fix case when time function gets NULL argument