CVE-2026-98886: drm/gma500: return errors from Oaktrail HDMI I2C reads

In the Linux kernel, the following vulnerability has been resolved:

drm/gma500: return errors from Oaktrail HDMI I2C reads

xferread() waits for the HDMI I2C transaction to reach I2CTRANSACTIONDONE, but it ignores both timeout and signal returns from waitforcompletioninterruptibletimeout(). If the interrupt never advances the transaction state, the loop can wait forever.

Return -ETIMEDOUT when the completion wait expires, propagate interrupted waits, and make the I2C masterxfer callback return the first transfer error instead of reporting a successful message count.