[SYCL] Fix array initialization after InitializedEntity API change (#36056)
Update addSimpleArrayInit to use InitializeMemberImplicit() instead of
InitializeMember() to properly indicate implicit member initialization.
This change is required after upstream commit 45ac2db4e5a5 refactored
InitializedEntity booleans into enums and split InitializeMember() into
separate functions for normal vs implicit initialization.
Without this fix, array kernel parameters fail with "array initializer
must be an initializer list" error because the initialization system no
longer recognizes this as an implicit initialization that allows array
copy operations.
Fixes: Clang::CodeGenSYCL/array-kernel-param.cpp test failure
Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>