crank libc major to reduce issues if users update from 7.8 and then have

to backout (as I had to do and ran into this). discussed with tb@ deraadt@

If you move from 7.8 to -current and run into problems and need to go
back to 7.8, you'll still have a libc.so.102.2 using syscalls that
weren't available in a 7.8 kernel. If it's the same major and higher
minor it'll be used in preference by the 7.8 binaries so anything
using __pledge_open will fail, bad system call, until you figure it
out, boot single-user, remove the newer libc and reboot/ldconfig.

If libc is bumped, users that were on 7.8 or a snap before pledge
changes before they updated, who then need to backout, won't have that
problem.

lib/libc/shlib_version

@@ -1,4 +1,4 @@
-major=102
-minor=2
+major=103
+minor=0
 # note: If changes were made to include/thread_private.h or if system calls
 # were added/changed then librthread/shlib_version must also be updated.