Force rebuild linker.config.pb even after a build error

After a build failure of linker.config.pb, we must manually remove
the temp.pb file to resume the build again after fixing the error.
By adding '--force' flag, the script will overwrite the existing
temp.pb file.

Bug: na
Test: build after an error for linker.config.pb
Change-Id: If51ba8291de49a7c0bed8771d702f61c904d3455

linkerconfig/linkerconfig.go

@@ -98,6 +98,7 @@ func BuildLinkerConfig(ctx android.ModuleContext, builder *android.RuleBuilder,
 	builder.Command().
 		BuiltTool("conv_linker_config").
 		Flag("proto").
+		Flag("--force").
 		FlagWithInput("-s ", input).
 		FlagWithOutput("-o ", interimOutput)