Add detailed status register printing and unlocking for all ATMEL AT25* chips

Add support for Atmel AT25DF081A and AT25DQ161.

Some chips require EWSR before WRSR, others require WREN before WRSR,
and some support both variants. Add feature_bits to select the correct
SPI command, and default to EWSR.

Corresponding to flashrom svn r1115.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Tested-by: Steven Rosario
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
7 files changed