toolchain: gcc: switch default to 13

Use GCC 13 instead of GCC 12 by default.

All target kernels are building with GCC 13.
Most packages from the feed are building fine.

The root file systems is getting a little bit smaller for MIPS 32 BE
and aarch64.

With GCC 12 I got these sizes for lantiq/xrx200:
7,005,867 openwrt-lantiq-xrx200-tplink_tdw8970-initramfs-kernel.bin

With GCC 13 I got these sizes for lantiq/xrx200:
6,989,754 openwrt-lantiq-xrx200-tplink_tdw8970-initramfs-kernel.bin

With GCC 12 I got these sizes for armsr/armv8:
13,083,836 openwrt-armsr-armv8-generic-ext4-combined.img.gz
 4,900,240 openwrt-armsr-armv8-generic-ext4-rootfs.img.gz
20,142,592 openwrt-armsr-armv8-generic-kernel.bin

With GCC 13 I got these sizes for armsr/armv8:
13,068,966 openwrt-armsr-armv8-generic-ext4-combined.img.gz
 4,893,078 openwrt-armsr-armv8-generic-ext4-rootfs.img.gz
20,142,592 openwrt-armsr-armv8-generic-kernel.bin

Signed-off-by: Nick Hainke <vincent@systemli.org>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

toolchain/gcc/Config.in

@@ -2,7 +2,7 @@
 
 choice
 	prompt "GCC compiler Version" if TOOLCHAINOPTS
-	default GCC_USE_VERSION_12
+	default GCC_USE_VERSION_13
 	help
 	  Select the version of gcc you wish to use.
 

toolchain/gcc/Config.version

@@ -2,13 +2,13 @@ config GCC_VERSION_11
 	default y if GCC_USE_VERSION_11
 	bool
 
-config GCC_VERSION_13
-	default y if GCC_USE_VERSION_13
+config GCC_VERSION_12
+	default y if GCC_USE_VERSION_12
 	bool
 
 config GCC_VERSION
 	string
 	default EXTERNAL_GCC_VERSION	if EXTERNAL_TOOLCHAIN && !NATIVE_TOOLCHAIN
 	default "11.3.0"	if GCC_VERSION_11
-	default "13.2.0"	if GCC_VERSION_13
-	default "12.3.0"
+	default "12.3.0"	if GCC_VERSION_12
+	default "13.2.0"