i2c-qcom-geni: Calculate transfer timeout based on payload size

Large I2C transfers gets timed out, which can take more than
1 second for completion. To support such large transfers,
calculate transfer completion timeout based on the payload size.

Change-Id: Iccb8466ae334ba2940588528be18235f63f2fddd
Signed-off-by: Shrey Vijay <shreyv@codeaurora.org>