Revert "serial: 8250: Let drivers request full 16550A feature probing"

This reverts commit e6da7808 which is
commit 9906890c upstream.  This changes
the kernel API and is not needed at all in the 5.10.y branch and will be
reverted upstream as well.

Change-Id: I7d629d3765be366b77aafabf0e89fac7a5aa73b9
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>