i2c: sh_mobile: check timing parameters for valid range

i2c: sh_mobile: check timing parameters for valid range

Due to misconfiguration, it can happen that the calculated timing
parameters are out of range. Bail out if that happens. We can also
simplify some logic later because of the verified value. Also, make the
printouts of the values more precise by adding the hex-prefixes.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
(cherry picked from commit 7663ebefca8079ef0fd2fff1047d3d10af654c78)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>