[media] rc-core: fix dib0700 scancode generation for RC5

[media] rc-core: fix dib0700 scancode generation for RC5

[ Upstream commit 4d298b8539ed59f1d69d3aa6e41a2c4908137612 ]

commit af3a4a9bbeb0 ("[media] dib0700: NEC scancode cleanup") cleaned
up the NEC scancode logic but overlooked the RC5 case.

This patch brings the RC5 case in line with the NEC code and makes
the struct self-documenting.

Signed-off-by: David Härdeman <david@hardeman.nu>
Reported-by: David Cimbůrek <david.cimburek@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>