gcc: Add GCC 12.2 package files

Also updates build scripts.

gcc/docker.sh

@@ -1,12 +1,13 @@
 #!/bin/bash
+set -e
 
 THIS=$(readlink -e $0)
 
-mkdir build
-cd build
+mkdir gcc/build
+cd gcc/build
 /src/gcc/configure --enable-languages=c,c++ --disable-multilib
 make -j$(nproc)
 
-mkdir gcc-$1
+mkdir gcc-$1 | true
 make -j$(nproc) install DESTDIR=/src/gcc-$1
 cp $THIS /src/gcc-$1