A firmware file can contains more than one section with secure type, so
use secure information from efuse to choose the one with matched
cryptography method. Then choose key data from MSS poll (multiple security
section pool; see below picture) according to key_index from efuse.

Note that the size of MSS pool isn't included in section size defined
in firmware header, so we also need to parse header of MSS pool to get
its size as shift to parse next section.

If secure boot isn't supported by current hardware, the first secure
section will be adopted, and no need additional process to key data.

  +---------------------------+
  |      firmware header      |
  |                           |
  | +-----------------------+ |
  | | section type/size * N-|-|-------+
  | | ...                   | |       |
  | +-----------------------+ |       |
  +---------------------------+       |
  :                           :       |
  +---------------------------+ -\    |
  | secure section type (ID:9)|  |    |
  |                           |  | <--+
  |                           |  |
  +---------------------------+ -/
  |MSS Pool for above section |
  |                           |
  |                           |
  +---------------------------+
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240204012627.9647-4-pkshih@realtek.com