build: Provide clang-14 for Debian12

build: Provide clang-14 for Debian12

checkstyle.sh assumes clang-format-11 but allows it to be overridden.
Debian12 ships with a minimal version of clang-14, so set the correct
version for checkstyle.

Before:
$ make checkstyle
extras/scripts/checkstyle.sh: line 41: --version: command not found
make: *** [Makefile:720: checkstyle] Error 127

After:
$ make checkstyle
Debian clang-format version 14.0.6
*******************************************************************
* CHECKSTYLE SUCCESSFULLY COMPLETED
*******************************************************************

Type: make
Fixes: 712fc0308981c61444e593d6bcc2ad62102c726d
Change-Id: I0c58456477011397115810dab825865b5850d10d
Signed-off-by: pim@ipng.nl