Move NN_TRY macro out of struct initialization

NNAPI NN_TRY macros use Statement Expressions (a GNU extension) to
propagate errors. However, a "return" statement in a Statement
Expression can lead to memory leaks when the Statement Expression is
being used to initialize a member of a struct. Specifically, when one member of a struct is already initialized, and a Statement Expression used to initialize a subsequent member early-returns, the previously initialized members will not have their destructors called.

This CL moves any NN_TRY macro out of struct initialization to avoid any
potential memory leaks.

Bug: 230500484
Test: mma
Test: presubmit
Change-Id: I3493fd4764f8eacc86750e6414e62bc891abaccd