MIPS: No need to select ARCH_SUPPORTS_MSI

MIPS: No need to select ARCH_SUPPORTS_MSI

Commit c24a8a7a9988 ("MIPS: Netlogic: Add MSI support for XLP") added
"select ARCH_SUPPORTS_MSI". But the Kconfig symbol ARCH_SUPPORTS_MSI was
already removed in v3.12, so that select is a nop. Drop it.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Jayachandran C <jchandra@broadcom.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/6521/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>