pkgsCross.avr.buildPackages.gcc{10,11}: avoid log limit on hydra

When upgrading from gcc 9 to 10, avr-gcc started to hit the hydra log
limit, preventing the binary cache from being populated.

This commit tries to workaround this issue by passing `-s` to make for
avr-gcc 10 and 11 which seem to exhibit this problem.

Reference #135605.

pkgs/development/compilers/gcc/10/default.nix

@@ -147,6 +147,7 @@ stdenv.mkDerivation ({
     else "")
       + lib.optionalString targetPlatform.isAvr ''
             makeFlagsArray+=(
+               '-s' # workaround for hitting hydra log limit
                'LIMITS_H_TEST=false'
             )
           '';

pkgs/development/compilers/gcc/11/default.nix

@@ -152,6 +152,7 @@ stdenv.mkDerivation ({
     else "")
       + lib.optionalString targetPlatform.isAvr ''
             makeFlagsArray+=(
+               '-s' # workaround for hitting hydra log limit
                'LIMITS_H_TEST=false'
             )
           '';