Add a 'reconfigure' make target

Reviewed-by: NTim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5197)

Configurations/descrip.mms.tmpl

@@ -553,6 +553,9 @@ configdata.pm : $(SRCDIR)Configure $(SRCDIR)config.com {- join(" ", @{$config{bu
         @ WRITE SYS$OUTPUT "*************************************************"
         @ PIPE ( EXIT %X10000000 )
 
+reconfigure reconf:
+	perl configdata.pm -r -v
+
 {-
   use File::Basename;
   use File::Spec::Functions qw/abs2rel rel2abs catfile catdir/;

Configurations/unix-Makefile.tmpl

@@ -793,6 +793,9 @@ configdata.pm: $(SRCDIR)/Configure $(SRCDIR)/config {- join(" ", @{$config{build
 	@echo "**************************************************"
 	@false
 
+reconfigure reconf:
+	$(PERL) configdata.pm -r -v
+
 {-
   use File::Basename;
   use File::Spec::Functions qw/:DEFAULT abs2rel rel2abs/;

Configurations/windows-makefile.tmpl

@@ -378,6 +378,9 @@ configdata.pm: "$(SRCDIR)\Configure" {- join(" ", map { '"'.$_.'"' } @{$config{b
 	@echo "**************************************************"
 	@exit 1
 
+reconfigure reconf:
+	"$(PERL)" configdata.pm -r -v
+
 {-
  use File::Basename;
  use File::Spec::Functions qw/:DEFAULT abs2rel rel2abs/;

INSTALL

@@ -1039,6 +1039,11 @@
  uninstall
                 Uninstall all OpenSSL components.
 
+ reconfigure
+ reconf
+                Re-run the configuration process, as exactly as the last time
+                as possible.
+
  update
                 This is a developer option. If you are developing a patch for
                 OpenSSL you may need to use this if you want to update