hptrr(4): Stop checking for failures from malloc(M_WAITOK)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D45852
(cherry picked from commit 92b0370ec65d5287a1deec84fd513e320a8da736)
(cherry picked from commit e4de0a965faaff171e6061714478c8f4eaec8cb1)