Modernize usage of 'macOS' in doc and comments

Apple changed the spelling of its operating system again, to "macOS",
effective with macOS 10.12 Sierra (2016-09-20).  Change Emacs
documentation and comments to match this.  Stick with older OS
spellings ("OS X", "Mac OS X") when talking about older releases where
the older names are more correct.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/coding.c b/src/coding.c
index 9f709bea24c..3e4af722e4c 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -122,7 +122,7 @@ END-OF-LINE FORMAT
   How text end-of-line is encoded depends on operating system.  For
   instance, Unix's format is just one byte of LF (line-feed) code,
   whereas DOS's format is two-byte sequence of `carriage-return' and
-  `line-feed' codes.  MacOS's format is usually one byte of
+  `line-feed' codes.  Classic Mac OS's format is usually one byte of
   `carriage-return'.
 
   Since text character encoding and end-of-line encoding are