regmap: Check readable regs in _regmap_read
regmap: Check readable regs in _regmap_read

Check if regs are readable.

Signed-off-by: Michal Simek <b20e59da6aeb5cea6c82b021069d69f63616c55d@xilinx.com>
Signed-off-by: Mark Brown <b51b9a92386687a9ac927cebfa0f978adeb8cea5@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs