chflags: Alias nocache to noucache for consistency

Event:			EuroBSDcon 2026
Requested by:		fuz
Reviewed by:		fuz, rmacklem
Differential Revision:	https://reviews.freebsd.org/D59588

bin/chflags/chflags.1

@@ -29,7 +29,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd August 26, 2026
+.Dd September 12, 2026
 .Dt CHFLAGS 1
 .Os
 .Sh NAME
@@ -130,7 +130,7 @@ The following keywords are currently defined:
 .Bl -tag -offset indent -width ".Cm opaque"
 .It Cm arch , archived
 set the archived flag (super-user only)
-.It Cm nocache
+.It Cm nocache, noucache
 set the nocache flag (owner or super-user only)
 .It Cm nodump
 set the nodump flag (owner or super-user only)

lib/libc/gen/strtofflags.c

@@ -81,11 +81,10 @@ static struct {
 	{ "nousparse",		0, UF_SPARSE	},
 	{ "nosystem",		0, UF_SYSTEM	},
 	/* Needed for some Linux cross-build that uses a stale stat.h. */
-#ifdef UF_NOCACHE
 	{ "nousystem",		0, UF_SYSTEM	},
+#ifdef UF_NOCACHE
+	{ "nocache",		1, UF_NOCACHE	},
 	{ "noucache",		1, UF_NOCACHE	}
-#else
-	{ "nousystem",		0, UF_SYSTEM	}
 #endif
 };
 #define nmappings	(sizeof(mapping) / sizeof(mapping[0]))