Add debug ramdisk variant

A module will be installed to debug_ramdisk (or
debug_ramdisk/first_stage_ramdisk if recovery as boot is true) if
debug_ramdisk is set to true.

Bug: 184004542
Test: soong test
Change-Id: Ic5a4d27407e506fffa462de2149e0785f11b2ac7
diff --git a/sh/sh_binary.go b/sh/sh_binary.go
index 6623381..42d5680 100644
--- a/sh/sh_binary.go
+++ b/sh/sh_binary.go
@@ -210,6 +210,10 @@
 	return proptools.Bool(s.properties.Vendor_ramdisk_available) || s.ModuleBase.InstallInVendorRamdisk()
 }
 
+func (s *ShBinary) DebugRamdiskVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
 func (s *ShBinary) RecoveryVariantNeeded(ctx android.BaseModuleContext) bool {
 	return proptools.Bool(s.properties.Recovery_available) || s.ModuleBase.InstallInRecovery()
 }