Revert "Split the x86 host toolchain into glibc and musl variants"

This reverts commit 4fb4ef2242.

Reason for revert: crossed with aosp/1775072

Change-Id: Ied922850b810d82627ba4f9ee42f672cfe286c91

android/paths.go

@@ -1667,7 +1667,7 @@ func pathForInstall(ctx PathContext, os OsType, arch ArchType, partition string,
 		partionPaths = []string{"target", "product", ctx.Config().DeviceName(), partition}
 	} else {
 		osName := os.String()
-		if os == Linux || os == LinuxMusl {
+		if os == Linux {
 			// instead of linux_glibc
 			osName = "linux"
 		}