dt-bindings: Add an entry for Purism SPC

Add an entry for Purism, SPC

Signed-off-by: Angus Ainslie (Purism) <angus@akkea.ca>
1 job for f/linux-next/dt in 11 minutes and 1 second (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #12433
librem5
build:aarch64

00:11:01