Defer the January 19, 2038 date limit in UFS1 filesystems to February 7, 2106
Standardize the definition of a UFS dinode.
Differential Revision: https://reviews.freebsd.org/D48472
(cherry picked from commit 1111a44301da39d7b7459c784230e1405e8980f8)
(cherry picked from commit aa90fbed151de512ab6e59f75df009533a15751f)
(cherry picked from commit 256389eaf158acaf67f0530764be8af68edee78c)
(cherry picked from commit 6cd973d903c8f214d84daf91eb75047631bf1618)
(cherry picked from commit e1ebda4458bbaf7d85fb803e20f3afc5441f24d9)
(cherry picked from commit 6f87402a02f0801942fe8f0d9a8f7f3e04dfbb01)
Approved-by: re (cperciva)