common : fix missing-noreturn warnings when compiling with clang 21 (#22702)

common/arg.cpp:3719:9: error: function 'operator()' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
     3719 |         [](common_params & /*params*/, int /*value*/) {
          |         ^
    common/arg.cpp:3726:9: error: function 'operator()' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
     3726 |         [](common_params & /*params*/, int /*value*/) {
          |         ^
    common/arg.cpp:3733:9: error: function 'operator()' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
     3733 |         [](common_params & /*params*/, int /*value*/) {
          |         ^
    common/arg.cpp:3740:9: error: function 'operator()' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
     3740 |         [](common_params & /*params*/, int /*value*/) {
          |         ^
    common/arg.cpp:3747:9: error: function 'operator()' could be declared with attribute 'noreturn' [-Werror,-Wmissing-noreturn]
     3747 |         [](common_params & /*params*/, int /*value*/) {
          |         ^

Signed-off-by: Adrien Gallouët <angt@huggingface.co>