staging: rtl8188eu: merge two functions

All that rtw_hal_read_chip_info does is call _ReadPROMContent. Merge the
two functions.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20210718173610.894-1-martin@kaiser.cx


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>