tools: build: use correct lib name for libtracefs feature detection

Use libtracefs as package name to lookup the CFLAGS for libtracefs. This
makes it possible to use the distro specific path as include path for
the header file.

Link: https://lkml.kernel.org/r/20240617-rtla-build-v1-1-6882c34678e8@suse.de



Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>