Merge the EFUSE_ShadowMapUpdate function into ReadAdapterInfo8188EU, which
is the only caller.

Merging the two functions makes it clearer that eeprom->efuse_eeprom_data
is in fact a temporary buffer that stores info read from efuses.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220709171000.180481-5-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>