LIBSSH2_ERROR_CHANNEL_WINDOW_FULL: add new error code

In order to signal that the requested operation can not succeed
because the receiving window had been exhausted, the error code
LIBSSH2_ERROR_BUFFER_TOO_SMALL has been reused but I have found
that in certain context it may be ambigous.

This patch introduces a new error code,
LIBSSH2_ERROR_CHANNEL_WINDOW_FULL, exclusive to signal that condition.
2 files changed