Allow gzcat as an alias for gzip's -dc mode.

This gets us closer to toybox tar (and toybox gzip/gzcat).

Test: treehugger
Change-Id: If934270439b258eae55cdd3e97ac0e83b1c79c70
diff --git a/ui/build/paths/config.go b/ui/build/paths/config.go
index c9946e2..11939e9 100644
--- a/ui/build/paths/config.go
+++ b/ui/build/paths/config.go
@@ -88,6 +88,7 @@
 	"getopt":   Allowed,
 	"git":      Allowed,
 	"grep":     Allowed,
+	"gzcat":    Allowed,
 	"gzip":     Allowed,
 	"hexdump":  Allowed,
 	"jar":      Allowed,