input: synaptics_fw_update: Add necessary delay for polling mode

2013.08.27
- Fixed i2c goes down if driver does lockdown during system bootup
  when device is communicated using polling mode.
  The reason is that driver cannot access to device immediately after
  command erase all.

Signed-off-by: Alexandra Chin <alexandra.chin@tw.synaptics.com>
Change-Id: Ieff08ee390a00100ed04dcf102ed22932c707b81
Git-commit: 9e65e64c4e12afdc3e49b7bf0a7093f091fd4f31
Git-repo: git://github.com/synaptics-touch/msm-3.4.git


[amaloche@codeaurora.org: Modified commit message for proper form]
Signed-off-by: Amy Maloche <amaloche@codeaurora.org>