copyright/license: Add missing file extensions

Proper file extensions help 'copyright header checker' find files
that should contain copyright info. Extensions also clearly indicate
file type, and help to fit in with the file naming convention.

Signed-off-by: Rafal Stefanowski <rafal.stefanowski@intel.com>

Makefile

@@ -27,16 +27,16 @@ endif
 endif
 
 archives:
-	@tools/pckgen $(PWD) tar zip
+	@tools/pckgen.sh $(PWD) tar zip
 
 rpm:
-	@tools/pckgen $(PWD) rpm --debug
+	@tools/pckgen.sh $(PWD) rpm --debug
 
 srpm:
-	@tools/pckgen $(PWD) srpm
+	@tools/pckgen.sh $(PWD) srpm
 
 deb:
-	@tools/pckgen $(PWD) deb --debug
+	@tools/pckgen.sh $(PWD) deb --debug
 
 dsc:
-	@tools/pckgen $(PWD) dsc
+	@tools/pckgen.sh $(PWD) dsc