.golangci.yml: disable varcheck and deadcode

varcheck and deadcode conflict with unused, creating
a different output file (reporting the same errors) on
different runs. With code-climate reporting, this can
result in an equal number of false positives and false negatives
when comparing successive runs, with no node changes.

assets/.golangci.yml

@@ -237,7 +237,6 @@ linters:
   disable-all: true
   enable:
     - bodyclose
-    - deadcode
     - depguard
     - dogsled
     - dupl
@@ -265,15 +264,16 @@ linters:
     - unconvert
     - unparam
     - unused
-    - varcheck
     - whitespace
   # don't enable:
+  # - deadcode
   # - gochecknoglobals
   # - gochecknoinits
   # - gocyclo
   # - lll
   # - maligned
   # - prealloc
+  # - varcheck
 
 issues:
   # List of regexps of issue texts to exclude, empty list by default.