keymap: Update the list of Samsung Series 9 models

Currently, keymaps are provided only for the NP90X3A laptop. Samsung
introduced updated models, codenamed 900X3B, 900X3C, 900X4B, 900X4C,
which are currently not matched by udev rules. This patch includes the
newer modules in udev rules and move the samsung-n90x3a file defining
keys to a more generic samsung-series-9 file.

The patch was tested on a 900X4C laptop, and other people reported
that the rules also work for 900X3B and 900X3C ones.

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>