Add license headers to splitkb/aurora glcdfont.c files (#26382)

* Add license headers to splitkb/aurora glcdfont.c files

`qmk lint` requires a license header on every code file in a keyboard's
directory tree, but the three Aurora glcdfont.c files have none. Since
lint walks each parent directory of the target, this makes
`qmk lint -kb splitkb/aurora/{corne,lily58,sweep}/rev1` fail for every
user of those boards, including on keymaps they have no control over.

The three files are byte-identical copies of a Corne font, so use the
same `Copyright <year> QMK` attribution already used for the comparable
file in keyboards/helix/glcdfont.c rather than assigning authorship.

Lint now passes for all three boards.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* Update keyboards/splitkb/aurora/corne/glcdfont.c

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/splitkb/aurora/lily58/glcdfont.c

Co-authored-by: Joel Challis <git@zvecr.com>

* Update keyboards/splitkb/aurora/sweep/glcdfont.c

Co-authored-by: Joel Challis <git@zvecr.com>

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
Co-authored-by: Joel Challis <git@zvecr.com>

keyboards/splitkb/aurora/corne/glcdfont.c

@@ -1,3 +1,19 @@
+/* Copyright 2023 splitkb.com <support@splitkb.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include "progmem.h"
 
 // NOTE: This file is a copy of `crkbd/soundmonster/glcdfont.c`

keyboards/splitkb/aurora/lily58/glcdfont.c

@@ -1,3 +1,19 @@
+/* Copyright 2023 splitkb.com <support@splitkb.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include "progmem.h"
 
 // NOTE: This file is a copy of `crkbd/soundmonster/glcdfont.c`

keyboards/splitkb/aurora/sweep/glcdfont.c

@@ -1,3 +1,19 @@
+/* Copyright 2023 splitkb.com <support@splitkb.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include "progmem.h"
 
 // NOTE: This file is a copy of `crkbd/soundmonster/glcdfont.c`