Fix typo endianess -> endianness

Rename contrib/struct_endianess.py to contrib/struct_endianness.py, and
fix the typo everywhere. This is in preparation to call the script in
CI on all repositories.

Related: OS#5884
Change-Id: Idc4af9098ba1de26243464c772d6ea8be330646a
diff --git a/include/osmocom/gsm/protocol/gsm_03_41.h b/include/osmocom/gsm/protocol/gsm_03_41.h
index 1b399ae..f6c36ca 100644
--- a/include/osmocom/gsm/protocol/gsm_03_41.h
+++ b/include/osmocom/gsm/protocol/gsm_03_41.h
@@ -25,7 +25,7 @@
 		uint8_t update:4;
 		uint8_t code_lo:4;
 #elif OSMO_IS_BIG_ENDIAN
-/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianess.py) */
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
 		uint8_t gs:2, code_hi:6;
 		uint8_t code_lo:4, update:4;
 #endif
@@ -36,7 +36,7 @@
 		uint8_t language:4;
 		uint8_t group:4;
 #elif OSMO_IS_BIG_ENDIAN
-/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianess.py) */
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
 		uint8_t group:4, language:4;
 #endif
 	} dcs;
@@ -45,7 +45,7 @@
 		uint8_t total:4;
 		uint8_t current:4;
 #elif OSMO_IS_BIG_ENDIAN
-/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianess.py) */
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
 		uint8_t current:4, total:4;
 #endif
 	} page;
@@ -63,7 +63,7 @@
 		uint8_t update:4;
 		uint8_t code_lo:4;
 #elif OSMO_IS_BIG_ENDIAN
-/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianess.py) */
+/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
 		uint8_t gs:2, alert:1, popup:1, code_hi:4;
 		uint8_t code_lo:4, update:4;
 #endif