Input: stmfts - add optional reset GPIO support

Add support for an optional "reset-gpios" property. If present, the
driver drives the reset line high at probe time and releases it during
power-on, after the regulators have been enabled.

Signed-off-by: Petr Hodina <petr.hodina@protonmail.com>
Co-developed-by: David Heidelberg <david@ixit.cz>
Signed-off-by: David Heidelberg <david@ixit.cz>
Link: https://patch.msgid.link/20260409-stmfts5-v4-8-64fe62027db5@ixit.cz
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>