llvm-project-source.inc: fix end of line in triple variable

llvm-project-source.inc: fix end of line in triple variable

After the return statement, a "," is present while a ";" is expected.

This leads to something like:

...return "x86_64-poky-linux",

Fix this syntax error by replacing "," with a ";".

Signed-off-by: João Marcos Costa <joaomarcos.costa@bootlin.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>