build: print error code when command fail

vcbuild.bat

@@ -399,7 +399,7 @@ if errorlevel 1 echo "Could not create junction to 'out\%config%'." & exit /B
 if not defined sign goto licensertf
 
 call tools\sign.bat Release\node.exe
-if errorlevel 1 echo Failed to sign exe&goto exit
+if errorlevel 1 echo Failed to sign exe, got error code %errorlevel%&goto exit
 
 :licensertf
 @rem Skip license.rtf generation if not requested.
@@ -425,7 +425,7 @@ if "%use_x64_node_exe%"=="true" (
   %node_exe% tools\license2rtf.mjs < LICENSE > %config%\license.rtf
 )
 
-if errorlevel 1 echo Failed to generate license.rtf&goto exit
+if errorlevel 1 echo Failed to generate license.rtf, got error code %errorlevel%&goto exit
 
 :stage_package
 if not defined stage_package goto install-doctools
@@ -525,7 +525,7 @@ if errorlevel 1 goto exit
 
 if not defined sign goto upload
 call tools\sign.bat node-v%FULLVERSION%-%target_arch%.msi
-if errorlevel 1 echo Failed to sign msi&goto exit
+if errorlevel 1 echo Failed to sign msi, got error code %errorlevel%&goto exit
 
 :upload
 @rem Skip upload if not requested