PKGSYSTEM_ENABLE_FSYNC=0 disables fdatasync() calls on
update-mime-database. Testing shows that multitude of these
calls are made, and each individual call can have large overhead
with e.g. LUKS+usb-storage combination. This speeds up significantly
the trigger in some setups.

See also discussion in:
!39679

ref #14590

Simon F authored Jan 18, 2023 and alice committed Jan 18, 2023

(cherry picked from commit 142730a1)

(cherry picked from commit c360a747)