Partially reverted 08f1bbe0c7.
The host should have this flexibility, which is consistent to the cs_hold argument.
However, the user should know as less as possible about the host.
So the wrapper layer (esp_flash_spi_init.c) should cover this, helping to set cs_setup to 1, to meet the common requirements.
We used to manually specify the CS id. However after the SPI bus lock is
introduced, the lock is responsible to assign the CS lines and provide
the CS id. The esp_flash driver now depends on the ID assigned by the
SPI bus lock, the configuration field is deprecated.
There used to be dummy phase before out phase in common command
transactions. This corrupts the data.
The code before never actually operate (clear) the QE bit, once it finds
the QE bit is set. It's hard to check whether the QE set/disable
functions work well.
This commit:
1. Cancel the dummy phase
2. Set and clear the QE bit according to chip settings, allowing tests
for QE bits. However for some chips (Winbond for example), it's not
forced to clear the QE bit if not able to.
3. Also refactor to allow chip_generic and other chips to share the same
code to read and write qe bit; let common command and read command share
configure_host_io_mode.
4. Rename read mode to io mode since maybe we will write data with quad
mode one day.
