* src/netcf.c (ncf_if_free): do not clear the error flag
* src/netcf.c (ncf_if_free): do not clear the error flag

Allow calling ncf_if_free after an error in another ncf_* function happened
without losing that error. That makes unwinding from an error simpler for
application.

osier/netcf,osier/netcf,battlemidget/deprecated-mingw32-netcf,seanbruno/fbsd-netcf,battlemidget/deprecated-mingw32-netcf,hallyn/netcf,seanbruno/fbsd-netcf,hallyn/netcf,seanbruno/fbsd-netcf,emaste/netcf,emaste/netcf,hallyn/netcf,emaste/netcf,osier/netcf