[MEM] Add .reset_buffer() to prevent deadlocks on various error cases

[MEM] Add .reset_buffer() to prevent deadlocks on various error cases

This commit adds new API, .reset_buffer(), to prevent deadlocks on various error cases.

When some errors occurs, ne-host-inputservice.c and ne-inf.c used to emulate normal execution by explicitly calling return_buffer().
However, as output callback can be not called, deadlock situations often happen when the exact transition of buffer states is not performed.

So, this patch makes the buffer state to initial one on all error cases to reduce the complexity and prevent deadlocks.

Signed-off-by: Dongju Chae <dongju.chae@samsung.com>