package/gcc: fix ARC adc/sbc patterns handling in GCC 10.x

package/gcc: fix ARC adc/sbc patterns handling in GCC 10.x

There is a problem while building various packages with GCC 10.x for ARC:

----------------------------->8---------------------------
make[2]: *** [magick/libGraphicsMagick_la-analyze.lo] Error 1
make[2]: *** Waiting for unfinished jobs....
/tmp/ccFqDn0F.s: Assembler messages:
/tmp/ccFqDn0F.s:1586: Error: operand is not duplicate of the previous one for instruction 'adc'
----------------------------->8---------------------------

This failure happens on regular basis and can also be observed in:

http://autobuild.buildroot.net/results/c9d13a3659e3a45864f9622b29122e666f763c6e/
http://autobuild.buildroot.net/results/84edcdb0f5759fa587a5638e1bab18379ee1f3b2/
http://autobuild.buildroot.net/results/6f6acbb1a8708ad840a9361ee72b8d14699b44d9/

More details you can find on filed issue:
https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/issues/310
Fix:
https://github.com/foss-for-synopsys-dwc-arc-processors/gcc/commit/09944fba5bfb8e5543ce043c70d08222cf2f97ff

This fix was already added in commit
692829d967c30768859c9e043c15f45edda109ac ("toolchain: add upstream fix
for arc gcc") for the ARC-specific gcc version, but not for gcc 10.x,
which can be selected on ARC and exhibits the same problem.

Signed-off-by: Veronika Kremneva <kremneva@synopsys.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>