Input: vivaldi - convert to use sysfs_emit_at() API

Follow the advice of the Documentation/filesystems/sysfs.rst and show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the
value to be returned to user space.

Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Link: https://lore.kernel.org/r/202212071644171074630@zte.com.cn
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Input: extract ChromeOS vivaldi physmap show function

Let's introduce a common library file for the physmap show function
duplicated between three different keyboard drivers. This largely copies
the code from cros_ec_keyb.c which has the most recent version of the
show function, while using the vivaldi_data struct from the hid-vivaldi
driver. This saves a small amount of space in an allyesconfig build.

$ ./scripts/bloat-o-meter vmlinux.before vmlinux.after

add/remove: 3/0 grow/shrink: 2/3 up/down: 412/-720 (-308)
Function old new delta
vivaldi_function_row_physmap_show - 292 +292
_sub_I_65535_1 1057564 1057616 +52
_sub_D_65535_0 1057564 1057616 +52
e843419@49f2_00062737_9b04 - 8 +8
e843419@20f6_0002a34d_35bc - 8 +8
atkbd_parse_fwnode_data 480 472 -8
atkbd_do_show_function_row_physmap 316 76 -240
function_row_physmap_show 620 148 -472
Total: Before=285581925, After=285581617, chg -0.00%

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Stephen Boyd <swboyd@chromium.org> # coachz, wormdingler
Link: https://lore.kernel.org/r/20220228075446.466016-3-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>