DIF_INSTALLDEVICE returns almost immediately, while the device
installation continues in the background. It might take a while, before
all registry keys and values are populated.
Previously, wireguard-go waited for HKLM\SYSTEM\CurrentControlSet\
Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}\<id> registry key
only.
Followed by a SetInterfaceName() method of Wintun struct which tried to
access HKLM\SYSTEM\CurrentControlSet\Control\Network\
{4D36E972-E325-11CE-BFC1-08002BE10318}\<id>\Connection registry key
might not be available yet.
This commit loops until both registry keys are available before
returning from CreateInterface() function.
Signed-off-by: Simon Rozman <simon@rozman.si>
