misc: eeprom: Fix EWEN/EWDS/ERAL commands for 93xx56 and 93xx66

misc: eeprom: Fix EWEN/EWDS/ERAL commands for 93xx56 and 93xx66

commit 14374fbb3f06 ("misc: eeprom_93xx46: Add new 93c56 and 93c66
compatible strings") added support for 93xx56 and 93xx66 eeproms, but
didn't take into account that the write enable/disable + erase all
commands are hardcoded for the 6-bit address of the 93xx46.

This commit fixes the command word generation by increasing the number
of shifts as the address field grows, keeping the command intact.

Also, the check for 8-bit or 16-bit mode is no longer required as this
is already taken into account in the edev->addrlen field.

Signed-off-by: Markus Perkins <markus@notsyncing.net>
Link: https://patch.msgid.link/20251202104823.429869-3-markus@notsyncing.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>