Fix features/i386/64bit-avx512.xml

Fix features/i386/64bit-avx512.xml

This file's format is invalid, as it's missing some end quotes.

I noticed this because I tried to regenerate all the .dat files in
gdb/regformats/.  I got:

    sh ../../move-if-change ../regformats/i386/x32-avx.tmp ../regformats/i386/x32-avx.dat
    echo "# DO NOT EDIT: generated from i386/x32-avx512.xml" > ../regformats/i386/x32-avx512.tmp
    echo "name:`echo x32-avx512 | sed 's/-/_/g'`" >> ../regformats/i386/x32-avx512.tmp
    echo "xmltarget:x32-avx512.xml" >> ../regformats/i386/x32-avx512.tmp
    echo "expedite:rbp,rsp,rip" \
      >> ../regformats/i386/x32-avx512.tmp
    xsltproc --path "/home/pedro/gdb/mygit/src/gdb/features" --xinclude number-regs.xsl i386/x32-avx512.xml | \
      xsltproc sort-regs.xsl - | \
      xsltproc gdbserver-regs.xsl - >> ../regformats/i386/x32-avx512.tmp
    i386/64bit-avx512.xml:81: parser error : Unescaped '<' not allowed in attributes values
      <reg name="zmm11h" bitsize="256" type="v2ui128/>
      ^
    i386/64bit-avx512.xml:81: parser error : attributes construct error
      <reg name="zmm11h" bitsize="256" type="v2ui128/>
      ^
    i386/64bit-avx512.xml:81: parser error : Couldn't find end of Start Tag reg line 80
      <reg name="zmm11h" bitsize="256" type="v2ui128/>
      ^
    i386/64bit-avx512.xml:82: parser error : Unescaped '<' not allowed in attributes values
      <reg name="zmm12h" bitsize="256" type="v2ui128/>
      ^
    i386/64bit-avx512.xml:82: parser error : attributes construct error
      <reg name="zmm12h" bitsize="256" type="v2ui128/>
      ^
...
    i386/x32-avx512.xml:17: element include: XInclude error : could not load i386/64bit-avx512.xml, and no fallback was found
    -:1: parser error : Document is empty

    ^
    -:1: parser error : Start tag expected, '<' not found

    ^
    unable to parse -
    -:1: parser error : Document is empty

    ^
    -:1: parser error : Start tag expected, '<' not found

    ^
    unable to parse -
    make: *** [../regformats/i386/x32-avx512.dat] Error 6

Interestingly, gdb/expat manages to grok the broken file.

gdb/
2014-10-01  Pedro Alves  <palves@redhat.com>

	* features/i386/64bit-avx512.xml (zmm10h, zmm11h, zmm12h, zmm13h)
	(zmm14h): Add missing end quotes.