[FIX] pRemoteCharacteristicNotify Null-Check Logic

[yymin1022]

Summary

Fixed Null-Check Logic for pRemoteCharacteristicNotify

Description

• When use PT-210 Printer, pRemoteCharacteristicNotify Value is NULL.
• But at Line 850, it checks about if pRemoteCharacteristicData is NULL that is already done at Line 845.
• So it does not check about if pRemoteCharacteristicNotify is NULL so when we use PT-210 Printer, Library makes abort() Issue at Line 850.
• So I changed the Null-Check Logic for pRemoteCharacteristicNotify.