[gdb/config] Fix codespell warnings

Fix the following codespell warnings:
...
$ codespell --config gdb/contrib/setup.cfg gdb/config
gdb/config/djgpp/README:178: unitialized ==> uninitialized
gdb/config/djgpp/djconfig.sh:126: conatain ==> contain
...
and add gdb/config to the pre-commit codespell configuration.

Approved-By: Tom Tromey <tom@tromey.com>

.pre-commit-config.yaml

@@ -69,7 +69,7 @@ repos:
     rev: v2.4.1
     hooks:
     - id: codespell
-      files: '^(gdbsupport|gdbserver|gdb/(tui|target|data-directory|po|system-gdbinit|mi|syscalls|arch|regformats|compile|python|guile))/'
+      files: '^(gdbsupport|gdbserver|gdb/(tui|target|data-directory|po|system-gdbinit|mi|syscalls|arch|regformats|compile|python|guile|config))/'
       args: [--config, gdb/contrib/setup.cfg]
   - repo: local
     hooks:

gdb/config/djgpp/README

@@ -175,7 +175,7 @@ SOMETHING.tst (where SOMETHING is the name of the failed test).  You
 should compare each of the *.tst files with the corresponding *.out
 file and convince yourself that the differences do not indicate a real
 problem.  Examples of differences you can disregard are changes in the
-copyright blurb printed by GDB, values of unitialized variables,
+copyright blurb printed by GDB, values of uninitialized variables,
 addresses of global variables like argv[] and envp[] (which depend on
 the size of your environment), etc.
 

gdb/config/djgpp/djconfig.sh

@@ -123,7 +123,7 @@ do
 done
 
 # Now set the config shell. It is really needed, that the shell
-# points to a shell with full path and also it must conatain the
+# points to a shell with full path and also it must contain the
 # .exe suffix. I assume here, that bash is installed. If not,
 # install it. Additionally, the pathname must not contain a
 # drive letter, so use the /dev/x/foo format supported by versions