[1/4] acm: Remove the unused variable 'pri_path'

[1/4] acm: Remove the unused variable 'pri_path'

The variable 'pri_path' is assigned a value but is never used.
This triggers the following compiler warning:

src/acm.c:301:26: warning: variable 'pri_path' set but not used [-Wunused-but-set-variable]

Hence remove this variable.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>