Define additional symlinks and dirs for recovery partition

To match that of the make generated recovery partition.

Test: mount Soong generated recovery partition and compare with TARGET_RECOVERY_ROOT_OUT
Bug: 381888358
Change-Id: I39822027088895525ef473ad9797f410d45ec7cd
diff --git a/fsgen/util.go b/fsgen/util.go
index 9ab3ad8..3894c46 100644
--- a/fsgen/util.go
+++ b/fsgen/util.go
@@ -16,6 +16,7 @@
 
 import (
 	"android/soong/android"
+	"android/soong/filesystem"
 	"fmt"
 	"strconv"
 	"strings"
@@ -58,3 +59,12 @@
 
 	return recoveryDensity
 }
+
+// Returns a new list of symlinks with prefix added to the dest directory for all symlinks
+func symlinksWithNamePrefix(symlinks []filesystem.SymlinkDefinition, prefix string) []filesystem.SymlinkDefinition {
+	ret := make([]filesystem.SymlinkDefinition, len(symlinks))
+	for i, symlink := range symlinks {
+		ret[i] = symlink.CopyWithNamePrefix(prefix)
+	}
+	return ret
+}