use clamp() for counts in csi_?() handlers

The count to process is supposed to be between 1 and vc->vc_cols -
vc->state.x (or rows and .y). clamp() can be used exactly for this,
instead of ifs and min().

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-14-jirislaby@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>