Modified NPE and typo of abbreviation of log tag

There could be NPE issue when connecting LE audio device.
And I've modified typo according to the policy of log tag abbreviation in Telecom.

Test: When node is added after connecting to LE audio device
Bug: 293220012

Change-Id: I8b750fb58c1320101cac4116212f4b807b9b0d09
Signed-off-by: Junyeong Bak <junyeong.bak@samsung.com>