i2c: acpi: Add DELL0A86 to i2c_acpi_force_100khz_device_ids

The ELAN 04F3:3185 touchpad exposed as DELL0A86 on the Dell Inspiron
13 5310 intermittently exhibits excessive smoothing when the I2C bus
runs at 400 kHz. During an affected period pointer movement becomes
severely sluggish and sticky for tens of seconds.

The ACPI firmware configures the touchpad bus for 400 kHz. Add DELL0A86
to i2c_acpi_force_100khz_device_ids so that the bus runs at 100 kHz, as
is already done for other touchpads exhibiting the same excessive
smoothing problem.

With the quirk applied, the kernel reports that the firmware requested
400 kHz and that the bus is forced to 100 kHz. The problem did not recur
during extended heavy use, including an S4 hibernate/resume cycle.

An independent 2021 report from another Dell Inspiron 13 5310 user
describes the same intermittent sticky behavior and identifies the same
DELL0A86 / 04F3:3185 touchpad.

Link: https://www.reddit.com/r/linuxquestions/comments/nsso5b/help_needed_with_sticky_touchpad_spoiling_brand/

Signed-off-by: YuXin Xiao <xiaoyueyoqwq@gmail.com>
Assisted-by: Codex:ChatGPT-5.6-Sol
Assisted-by: OpenCode:Ox Alpha (x-preview-f-free)
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://patch.msgid.link/20260824181559.146133-1-xiaoyueyoqwq@gmail.com

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