(nxml-faces): Rename from nxml-highlighting-faces.

(nxml-faces): Rename from nxml-highlighting-faces.
Parent group is font-lock-faces.
(nxml-light-blue-color, nxml-dark-blue-color, nxml-green-color)
(nxml-sky-blue-color, nxml-dark-green-color, nxml-light-green-color):
(nxml-version): Remove.
(nxml-delimited-data, nxml-name, nxml-ref, nxml-delimiter)
(nxml-text, nxml-comment-content, nxml-comment-delimiter)
(nxml-processing-instruction-delimiter)
(nxml-processing-instruction-target)
(nxml-processing-instruction-content, nxml-cdata-section-delimiter)
(nxml-cdata-section-CDATA, nxml-cdata-section-content)
(nxml-char-ref-number, nxml-char-ref-delimiter, nxml-entity-ref-name)
(nxml-entity-ref-delimiter, nxml-tag-delimiter, nxml-tag-slash)
(nxml-element-prefix, nxml-element-colon, nxml-element-local-name)
(nxml-attribute-prefix, nxml-attribute-colon)
(nxml-attribute-local-name, nxml-namespace-attribute-xmlns)
(nxml-namespace-attribute-colon, nxml-namespace-attribute-prefix)
(nxml-attribute-value, nxml-attribute-value-delimiter)
(nxml-namespace-attibute-value)
(nxml-namespace-attribure-value-delimiter)
(nxml-prolog-literal-delimiter, nxml-prolog-literal-content)
(nxml-prolog-keyword, nxml-markup-declaration-delimiter, nxml-hash)
(nxml-glyph): Rename, removing -face suffix.
Inherit from existing font-lock faces.
(nxml-apply-fontify-rule, nxml-char-ref-display-extra):
Use new face names.