[Mutt] #3575: smime_keys.pl fails on filenames with spaces

#3575: smime_keys.pl fails on filenames with spaces
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 Reporter:  Y_Plentyn  |       Owner:  mutt-dev
     Type:  defect     |      Status:  new     
 Priority:  minor      |   Milestone:          
Component:  crypto     |     Version:          
 Keywords:             |  
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 Forwarding from  http://bugs.debian.org/658324 :

 {{{
 Dear Maintainer,

 I recently needed to update by smime-keyring with a new version of my own
 certificate to a new one, and saved it to a file named
 "cacert kandre <at> ak-online.be renewed.p12".

 Unfortunately 'smime_keys add_p12 "cacert kandre <at> ak-online.be
 renewed.p12"'
 failed with the return code 256 from openssl and a dump of it's
 commandline
 options.

 I looked into smime_keys and found that the perl-script builds the command
 in line 156 directly from $ARGV[1]:

 >>>> snip <<<<
 156:    my $cmd = "$opensslbin pkcs12 -in $ARGV[1] -out $pem_file";
 157:        system $cmd and die "'$cmd' returned $?";
 >>>> snip <<<<