Change in flashrom[master]: programmer.h: remove unused interfaces of bitbang_spi_master

[Xiang Wang (Code Review)]

Attention is currently required from: Stefan Reinauer, Edward O'Callaghan, Angel Pons.
Xiang Wang has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/49256 )

Change subject: programmer.h: remove unused interfaces of bitbang_spi_master
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Patch Set 6:

(1 comment)

Patchset:

PS3: 
The meaning of the set_sck_set_mosi/set_sck_get_miso interface is ambiguous

set_sck_set_mosi should be set_mosi befor set_sck
set_sck_get_miso should be get_miso after set_sck

The replacement function in the absence of the set_sck_set_mosi interface is also wrong
> static void bitbang_spi_set_sck_set_mosi(const struct bitbang_spi_master * const master, int sck, int mosi)
> {
>    if (master->set_sck_set_mosi) {
>    	master->set_sck_set_mosi(sck, mosi);
>    	return;
>    }
>
> master->set_sck(sck);
>    master->set_mosi(mosi);
> }