Drop unnecessary semicolon from end of file

Remove unnecessary semicolon to avoid a warning about C++98
incompatibility:
error: extra ';' outside of a function is incompatible with
C++98 [-Werror,-Wc++98-compat-extra-semi]

Test: Built an AIDL interface with trace.h methods, ran on device, collected traces.

Change-Id: I307a36eeef861d4c28aa85dc3e0b15500bfac7c8