MediaTek proprietary license

[armijnhemel]

Description

This one is quite close to proprietary-license_663.RULE but there are a few differences that throws Scancode off a bit, so perhaps it is best to add it as another license:

https://github.com/MediaTek-Labs/mt3620_m4_software/blob/master/MT3620_M4_Sample_Code/OS_HAL/src/os_hal_mbox.c

[DennisClark]

new license LicenseRef-scancode-mediatek-proprietary-2005 created in DejaCode enterprise and public. Proprietary Free.

@AyanSinhaMahapatra please synchronize when you have time, thanks.

[AyanSinhaMahapatra]

Added in #4478, added also to licensedb and license-expression v30.4.4 , closing.