linux-firmware: add firmware for qat_420xx devices

Add firmware images for Intel QAT 420xx crypto/compression accelerators.

Firmware version: 0.9.0

Release notes for this firmware are reported at [1].

$ sha256sum qat_420*
32f0d78fd739a392dc9cd1be0de1ad4f014137ed0cd44bcb1857101f80b681e8  qat_420xx.bin
db264ee400c2c42fb2b4ce0f7675e142810f3ce4a01da70a8ce91f5a0b838d6b  qat_420xx_mmp.bin

Link: https://intel.github.io/quickassist/RN/In-Tree/index.html [1]
Signed-off-by: Nancy Garala <nancy.garala@intel.com>

WHENCE

@@ -4466,6 +4466,8 @@ File: qat_4xxx.bin
 File: qat_4xxx_mmp.bin
 File: qat_402xx.bin
 File: qat_402xx_mmp.bin
+File: qat_420xx.bin
+File: qat_420xx_mmp.bin
 
 Licence: Redistributable. See LICENCE.qat_firmware for details