Remove checks for hyphenated library names

This CL removes checks for directories whose names are FIDL libraries
with "." replaced by "-". Those used to exist in zircon/system/fidl, but
no longer (that directory still exists but it only has build rules, no
FIDL files).

Change-Id: I9634d3c1e23844fd6bfab4d9a11925a2a382c844
Reviewed-on: https://fuchsia-review.googlesource.com/c/fidlbolt/+/587298
Reviewed-by: Yifei Teng <yifeit@google.com>
diff --git a/backend/analyze.go b/backend/analyze.go
index 38f8ef5..9073a25 100644
--- a/backend/analyze.go
+++ b/backend/analyze.go
@@ -79,7 +79,7 @@
 // information to speed up future analyses.
 type libraryAnalyzer struct {
 	// Paths in which to search for FIDL library files. Given library foo.bar,
-	// the analyzer will check P/foo.bar and P/foo-bar for each path P in paths.
+	// the analyzer will check if $P/foo.bar/ exists for each path $P in paths.
 	// If one of these exists, it reads all descendent .fidl files.
 	paths []string
 	// Global cache of library information.
@@ -328,7 +328,11 @@
 		// directory named "vsdo" (fuchsia/zircon/vdso), not "zx".
 		return []string{"vdso"}
 	}
-	return []string{string(lib), strings.ReplaceAll(string(lib), ".", "-")}
+	// Currently this function always returns one result. It used to also return
+	// strings.ReplaceAll(string(lib), ".", "-") back when zircon/system/fidl/
+	// had FIDL files under that scheme. We are keeping the []string return type
+	// in case this needs to return multiple results again in the future.
+	return []string{string(lib)}
 }
 
 // isPlatform returns true if lib adheres to the naming scheme for platform