pkgtools/pkglint: update to 5.6.10

Changes since 5.6.9:

* ALTERNATIVES files are correctly checked now. Before, pkglint had
  suggested to remove the @PREFIX/ from the alternative, which was
  wrong and simply didn't work.

* Diagnostics about variable assignments are ordered to report the
  left-hand side first and then everything to the right of the
  assignment operator.

* The pkglint output is escaped properly to avoid sending unwanted
  escape sequences to the terminal.

* The items in .for loops are parsed taking "double" and 'single'
  quotes into account since bmake does it in the same way since 2015.

* In DESCR files, overly long lines are only warned about if they
  contain a space and therefore can be made shorter.

* In DESCR files, text like ${PREFIX} only gets a note if it refers
  to a commonly known pkgsrc variable. This avoids distraction when
  a package mentions ${prefix}/bin or ${template.property}.

* Lots of refactorings and small changes.

1 files changed, 8 insertions, 1 deletions

diff --git a/pkgtools/pkglint/files/shell.go b/pkgtools/pkglint/files/shell.go
index a83295704ff..93b20771071 100644
--- a/pkgtools/pkglint/files/shell.go
+++ b/pkgtools/pkglint/files/shell.go
@@ -10,6 +10,11 @@ import (
 
 // TODO: Can ShellLine and ShellProgramChecker be merged into one type?
 
+// ShellLine is either a line from a Makefile starting with a tab,
+// thereby containing shell commands to be executed.
+//
+// Or it is a variable assignment line from a Makefile with a left-hand
+// side variable that is of some shell-like type; see Vartype.IsShell.
 type ShellLine struct {
 	mkline MkLine
 }
@@ -293,7 +298,9 @@ func (shline *ShellLine) CheckShellCommandLine(shelltext string) {
 	}
 	setE := lexer.SkipString("${RUN}")
 	if !setE {
-		lexer.NextString("${_PKG_SILENT}${_PKG_DEBUG}")
+		if lexer.NextString("${_PKG_SILENT}${_PKG_DEBUG}") != "" {
+			line.Warnf("Use of _PKG_SILENT and _PKG_DEBUG is deprecated. Use ${RUN} instead.")
+		}
 	}
 
 	shline.CheckShellCommand(lexer.Rest(), &setE, RunTime)