tracing: uart: rename global variable named dev

MISRA-C Rule 5.3 states that identifiers in inner scope should
not hide identifiers in outer scope.

There is a global variable named "dev" to store which UART
device is being used the tracing backend. This name collides
with the parameter of same name in the ISR function. So rename
the global variable.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
1 file changed