Remove evil-mode and doom-emacs references from patches

These patches target GNU Emacs core; third-party package references
are unacceptable for upstream submission.

patch 0006: doom-modeline -> icon-based mode-lines; Evil-mode -> generic
patch 0007: fix hunk context hint (doom-modeline -> nerd-font icons)
patch 0008: Evil-mode block cursors -> Block-style cursors

The evil DEFSYM (Qns_ax_evil_next_line etc.) were already removed
by cd288e8.

patches/0006-doc-add-VoiceOver-accessibility-section-to-macOS-app.patch

@@ -88,7 +88,7 @@ index 6bd334f..6514dfc 100644
 +are fast.
 +@item
 +Mode-line text extraction handles only character glyphs.  Mode lines
-+using icon fonts (e.g., @code{doom-modeline} with nerd-font icons)
++using icon fonts (e.g., icon-based mode-lines)
 +produce incomplete accessibility text.
 +@item
 +The accessibility virtual element tree is rebuilt automatically on
@@ -101,7 +101,7 @@ index 6bd334f..6514dfc 100644
 +
 +  This support is available only on the Cocoa build; GNUstep has a
 +different accessibility model and is not yet supported;
-+@xref{GNUstep Support}.  Evil-mode block cursors are handled
++Block-style cursors are handled
 +correctly: character navigation announces the character at the cursor
 +position, not the character before it.
 +