mips: irq.c:114:19: error: unused variable 'desc' [-Werror=unused-variable]

[Naresh Kamboju]

Regression found on mips gcc-10 built with defconfig
Following build warnings / errors reported on linux next 20211027.

The bisect tool pointing to the following commit
The first bad commit:

commit 4cb6f4df976b288aa02bbb658d38e73d34d8231f
  irq: mips: simplify do_domain_IRQ()

metadata:
    git_describe: next-20211027
    git_repo: https://gitlab.com/Linaro/lkft/mirrors/next/linux-next
    git_short_log: ae5179317e79 (\"Add linux-next specific files for 20211027\")
    target_arch: mips
    toolchain: gcc-10

build error :
--------------
<stdin>:1559:2: warning: #warning syscall futex_waitv not implemented [-Wcpp]
arch/mips/kernel/irq.c: In function 'do_domain_IRQ':
arch/mips/kernel/irq.c:114:19: error: unused variable 'desc'
[-Werror=unused-variable]
  struct irq_desc *desc;
                   ^~~~
cc1: all warnings being treated as errors

Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>

build link:
-----------
https://builds.tuxbuild.com/205S9XOzkonL7F3xvY8YUO2l1QT/build.log

build config:
-------------
https://builds.tuxbuild.com/205S9XOzkonL7F3xvY8YUO2l1QT/config

# To install tuxmake on your system globally
# sudo pip3 install -U tuxmake
tuxmake --runtime podman --target-arch mips --toolchain gcc-10
--kconfig defconfig

--
Linaro LKFT
https://lkft.linaro.org