Fixed build with kernel 5.12 or newer. A macro with the name MODULE_SUPPORTED_DEVICE

had actually never been used by the kernel, and was removed in Kernel 5.12.
So a reference to that macro was removed from the kernel driver source
to avoid an “Unresolved symbol” error at compile time.

Improved printing of UTC/leap second info by mbgstatus. Now the time immediately after
the leap second is displayed because it may no be clear whether a leap second has been
inserted, or deleted, but in any case this is the time when the latest change in the
GPS/UTC offset comes into effect.

Added option -Q (query only) to mbgsvcd, so it can be run in the foreground without
updating the SHM segments.

The Kernel driver now releases all resources on exit after failing to probe a device.

Updated some library files to current versions.