[llvm-nm] Fix docs and help text for --print-size

The --print-size help text and documentation claimed that the size was
printed instead of the address, but this is incorrect. It is printed as
well as the address. This patch fixes this issue.

Reviewed by: MaskRay, mtrent, ruiu

Differential Revision: https://reviews.llvm.org/D63142

llvm-svn: 363136
diff --git a/llvm/docs/CommandGuide/llvm-nm.rst b/llvm/docs/CommandGuide/llvm-nm.rst
index b5bd756..278dd27 100644
--- a/llvm/docs/CommandGuide/llvm-nm.rst
+++ b/llvm/docs/CommandGuide/llvm-nm.rst
@@ -121,7 +121,7 @@
 
 .. option:: --print-size, -S
 
- Show symbol size instead of address.
+ Show symbol size as well as address (not applicable for Mach-O).
 
 .. option:: --size-sort