xen/gzip: Colocate gunzip code files

This patch moves the gunzip code files to common/gzip. Makefiles are adjusted
accordingly.

Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

docs/misra/exclude-list.json

@@ -118,7 +118,7 @@
             "comment": "Imported from Linux, ignore for now"
         },
         {
-            "rel_path": "common/inflate.c",
+            "rel_path": "common/gzip/inflate.c",
             "comment": "Imported from Linux, ignore for now"
         },
         {