Revert "Merge #171177: go-modules/packages: Improve `checkFlags` handling"

This reverts commit 361139c574, reversing
changes made to 77ee91f1d3.

This broke tests in some go packages, and at this point I don't want
further delays from figuring out what's wrong.  This probably won't
make it to 22.05.  Example failures:
  https://hydra.nixos.org/build/176551928
  https://hydra.nixos.org/build/176546993
but I think there were more among
  https://hydra.nixos.org/eval/1762178?compare=1762151#tabs-now-fail

pkgs/development/go-modules/generic/default.nix

@@ -180,22 +180,12 @@ let
       exclude+='\)'
 
       buildGoDir() {
-        local cmd="$1" dir="$2"
-
+        local d; local cmd;
+        cmd="$1"
+        d="$2"
         . $TMPDIR/buildFlagsArray
-
-        declare -a flags
-        flags+=($buildFlags "''${buildFlagsArray[@]}")
-        flags+=(''${tags:+-tags=${lib.concatStringsSep "," tags}})
-        flags+=(''${ldflags:+-ldflags="$ldflags"})
-        flags+=("-v" "-p" "$NIX_BUILD_CORES")
-
-        if [ "$cmd" = "test" ]; then
-          flags+=($checkFlags)
-        fi
-
         local OUT
-        if ! OUT="$(go $cmd "''${flags[@]}" $dir 2>&1)"; then
+        if ! OUT="$(go $cmd $buildFlags "''${buildFlagsArray[@]}" ''${tags:+-tags=${lib.concatStringsSep "," tags}} ''${ldflags:+-ldflags="$ldflags"} -v -p $NIX_BUILD_CORES $d 2>&1)"; then
           if ! echo "$OUT" | grep -qE '(no( buildable| non-test)?|build constraints exclude all) Go (source )?files'; then
             echo "$OUT" >&2
             return 1
@@ -253,7 +243,7 @@ let
       runHook preCheck
 
       for pkg in $(getGoDirs test); do
-        buildGoDir test "$pkg"
+        buildGoDir test $checkFlags "$pkg"
       done
 
       runHook postCheck

pkgs/development/go-packages/generic/default.nix

@@ -160,22 +160,12 @@ let
       exclude+='\)'
 
       buildGoDir() {
-        local cmd="$1" dir="$2"
-
+        local d; local cmd;
+        cmd="$1"
+        d="$2"
         . $TMPDIR/buildFlagsArray
-
-        declare -a flags
-        flags+=($buildFlags "''${buildFlagsArray[@]}")
-        flags+=(''${tags:+-tags=${lib.concatStringsSep "," tags}})
-        flags+=(''${ldflags:+-ldflags="$ldflags"})
-        flags+=("-v" "-p" "$NIX_BUILD_CORES")
-
-        if [ "$cmd" = "test" ]; then
-          flags+=($checkFlags)
-        fi
-
         local OUT
-        if ! OUT="$(go $cmd "''${flags[@]}" $dir 2>&1)"; then
+        if ! OUT="$(go $cmd $buildFlags "''${buildFlagsArray[@]}" ''${tags:+-tags=${lib.concatStringsSep "," tags}} ''${ldflags:+-ldflags="$ldflags"} -v -p $NIX_BUILD_CORES $d 2>&1)"; then
           if ! echo "$OUT" | grep -qE '(no( buildable| non-test)?|build constraints exclude all) Go (source )?files'; then
             echo "$OUT" >&2
             return 1
@@ -235,7 +225,7 @@ let
       runHook preCheck
 
       for pkg in $(getGoDirs test); do
-        buildGoDir test "$pkg"
+        buildGoDir test $checkFlags "$pkg"
       done
 
       runHook postCheck