Unbreak building of rustic_core-0.1.1 on OpenBSD (#27) (#28)

Issue was caused by a couple of configuration checks.

Co-authored-by: aawsome <37850842+aawsome@users.noreply.github.com>

src/error.rs

@@ -14,7 +14,7 @@ use std::{
     time::SystemTimeError,
 };
 
-#[cfg(not(any(windows, target_os = "openbsd")))]
+#[cfg(not(windows))]
 use nix::errno::Errno;
 
 use aes256ctr_poly1305aes::aead;
@@ -628,7 +628,7 @@ pub enum LocalErrorKind {
     FromWalkdirError(#[from] walkdir::Error),
     /// {0:?}#
     #[error(transparent)]
-    #[cfg(not(any(windows, target_os = "openbsd")))]
+    #[cfg(not(windows))]
     FromErrnoError(#[from] Errno),
     /// listing xattrs on {1:?}: {0}
     #[cfg(not(any(windows, target_os = "openbsd")))]
@@ -670,10 +670,10 @@ pub enum LocalErrorKind {
     /// failed to sync OS Metadata to disk: `{0:?}`
     SyncingOfOsMetadataFailed(std::io::Error),
     /// setting file permissions failed: `{0:?}`
-    #[cfg(not(any(windows, target_os = "openbsd")))]
+    #[cfg(not(windows))]
     SettingFilePermissionsFailed(std::io::Error),
     /// failed to symlink target {linktarget:?} from {filename:?} with {source:?}
-    #[cfg(not(any(windows, target_os = "openbsd")))]
+    #[cfg(not(windows))]
     SymlinkingFailed {
         linktarget: PathBuf,
         filename: PathBuf,