sensors: brcm: use non atomic sleeps instead of atomic delays

sensors: brcm: use non atomic sleeps instead of atomic delays

Do not use mdelay in non atomic contexts, use the appropriate
*sleep functions instead.

mdelay should be used only in atomic contexts, out from atomic it
keeps looping over the CPU wasting unnecessary resources.

Replace the mdelay's with:

 - usleep_range for 10us - 20ms delays,
 - msleep for over 20ms

Change-Id: Id03238f3918f43cb42c31ef258a12c3e7f4506a5
Reported-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>