ARM: shmobile: Remove obsolete intc.h

The last user of "intc.h" was removed in commit 9a986398

 ("ARM:
shmobile: Remove legacy SoC code for SH-Mobile AG5").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>