Fix leak when smartmatching against a coderef

Previously, when smartmatching against a code reference, the return
value would be leaked. This fixes that leak.

Author: Leont

pp_ctl.c

@@ -5888,17 +5888,13 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other, const bool copied)
           sm_any_sub:
             DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-CodeRef\n"));
             ENTER_with_name("smartmatch_coderef");
-            SAVETMPS;
             PUSHMARK(SP);
             PUSHs(d);
             PUTBACK;
             c = call_sv(e, G_SCALAR);
             SPAGAIN;
             if (c == 0)
                 PUSHs(&PL_sv_no);
-            else if (SvTEMP(TOPs))
-                SvREFCNT_inc_void(TOPs);
-            FREETMPS;
             LEAVE_with_name("smartmatch_coderef");
             RETURN;
         }

t/op/svleak.t

@@ -15,7 +15,7 @@ BEGIN {
 
 use Config;
 
-plan tests => 153;
+plan tests => 154;
 
 # run some code N times. If the number of SVs at the end of loop N is
 # greater than (N-1)*delta at the end of loop 1, we've got a leak
@@ -646,6 +646,9 @@ my $refcount;
 PERL
 }
 
+my $one = 1;
+leak 2, 0, sub { 1 ~~ sub { 1 + $one } }, 'Smartmatch doesn\'t leak';
+
 # the initial implementation of the require hook had some leaks
 
 sub hook::before  { $_[0] = "NoSuchFile2" if $_[0] =~/ NoSuch/;