board: cssi: Remove usage of common.h

Remove inclusion of common.h and add relevant
includes when necessary.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

board: MCR3000: Use lowercase filenames

Rename MCR3000.* to mcr3000.* to be more in line with
other boards.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

board: MCR3000: Use lowercase filenames

Rename MCR3000.* to mcr3000.* to be more in line with
other boards.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>