port_binary_distributable.tcl needs to normalize the case of the port name

[ryandesign (Ryan Carsten Schmidt)]

Now that MacPorts prevents you from specifying a nonexistent subport, port_binary_distributable.tcl fails if the port name is not specified with the correct capitalization:

$ ./port_binary_distributable.tcl -v imagemagick
ImageMagick does not have a subport 'imagemagick'
    while executing
"error "$portname does not have a subport '$supplied_subport'""
    (procedure "mportopen" line 64)
    invoked from within
"mportopen $portInfo(porturl) [list subport $portName] $variantInfo"
    (procedure "infoForPort" line 10)
    invoked from within
"infoForPort $portName $variantInfo"
    (procedure "check_licenses" line 4)
    invoked from within
"check_licenses $portName [array get variantInfo] $verbose"
    invoked from within
"exit [check_licenses $portName [array get variantInfo] $verbose]"
    (file "/Users/rschmidt/macports/macports-infrastructure/jobs/port_binary_distributable.tcl" line 336)

[ryandesign (Ryan Carsten Schmidt)]

Duplicate of #56161.