check_seapp: cleanup warning caught by clang tidy / static analyzer.

check_seapp.c:993:6: warning: Passed-by-value struct argument contains
uninitialized data (e.g., field: 'data')

Bug: 26936282
Test: WITH_TIDY=1 WITH_STATIC_ANALYZER=1 mm
Change-Id: I3fc2ca8f862356628864f2a37b8d39222c8d658a