docs: clarify wording in programming-language.rst

Clarify that the Linux kernel is written in C and improve
punctuation in the clang sentence.

Signed-off-by: Ariful Islam Shoikot <islamarifulshoikat@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260214132842.1161-1-islamarifulshoikat@gmail.com>
1 file changed