char: 88pm88x: add delay between enable and get gpadc measurement

after enabling the gpadc measurement, need little delay before reading
the measrement to verify that we get stable value.

Change-Id: Iacc72b01308b92027d6ae01c6def98ea359f6af9
Signed-off-by: Yaacov Hazan <yaacovh@marvell.com>
1 file changed