perlPackages.MHonArc: remove merged patch

diff --git a/lib/mhamain.pl b/lib/mhamain.pl

index 80980a2..c1259ce 100644

--- a/lib/mhamain.pl

+++ b/lib/mhamain.pl

@@ -1562,7 +1562,7 @@ sub signal_catch {

 ##

 sub defineIndex2MsgId {

     no warnings qw(deprecated);

-    if (!defined(%Index2MsgId)) {

+    unless (%Index2MsgId) {

 	foreach (keys %MsgId) {

 	    $Index2MsgId{$MsgId{$_}} = $_;

 	}

diff --git a/lib/mhopt.pl b/lib/mhopt.pl

index 02fb05e..939109b 100644

--- a/lib/mhopt.pl

+++ b/lib/mhopt.pl

@@ -865,7 +865,7 @@ sub update_data_1_to_2 {

 sub update_data_2_1_to_later {

     no warnings qw(deprecated);

     # we can preserve filter arguments

-    if (defined(%main::MIMEFiltersArgs)) {

+    if (%main::MIMEFiltersArgs) {

 	warn qq/         preserving MIMEARGS...\n/;

 	%readmail::MIMEFiltersArgs = %main::MIMEFiltersArgs;

 	$IsDefault{'MIMEARGS'} = 0;

      hash = "sha256-RX3HN07lnLdaBynlHO8vLFK0gYD3Odj9lW6hmIKBXzM=";

    };

    patches = [ ../development/perl-modules/mhonarc.patch ];

    outputs = [ "out" "dev" ]; # no "devdoc"

    installTargets = [ "install" ];