tests: lib: cbprintf: Added configuration without _Generic

Extended test to validate case when _Generic keyword is not used.

Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>

tests/lib/cbprintf_package/src/main.c

@@ -124,6 +124,7 @@ void test_main(void)
 	printk("alignof: int=%zu long=%zu ptr=%zu long long=%zu double=%zu long double=%zu\n",
 	       __alignof__(int), __alignof__(long), __alignof__(void *),
 	       __alignof__(long long), __alignof__(double), __alignof__(long double));
+	printk("%s C11 _Generic\n", Z_C_GENERIC ? "With" : "Without");
 
 	ztest_test_suite(cbprintf_package,
 			 ztest_unit_test(test_cbprintf_package)

tests/lib/cbprintf_package/testcase.yaml

@@ -10,6 +10,18 @@ tests:
     extra_configs:
       - CONFIG_CBPRINTF_COMPLETE=y
 
+  libraries.cbprintf_package_no_generic:
+    tags: cbprintf
+    integration_platforms:
+      - native_posix
+    platform_allow: >
+      qemu_arc_em qemu_arc_hs qemu_cortex_a53 qemu_cortex_m0 qemu_cortex_m3
+      qemu_cortex_r5 qemu_leon3 qemu_nios2 qemu_riscv32 qemu_riscv64 qemu_x86
+      qemu_x86_64 qemu_xtensa
+    extra_configs:
+      - CONFIG_CBPRINTF_COMPLETE=y
+      - CONFIG_COMPILER_OPT="-DZ_C_GENERIC=0"
+
   libraries.cbprintf_package_fp:
     tags: cbprintf
     integration_platforms: