pw_protobuf: Tweak documentation of name conflicts

Rearrange and reword part of the "Reserved-Word Conflicts" section of
docs.rst for better clarity and readability.

Change-Id: I198ff8029c2614f12599445519b379397018c5a2
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/99004
Reviewed-by: Ted Pudlik <tpudlik@google.com>
Commit-Queue: Matthias Guenther <mrguenther@google.com>
diff --git a/pw_protobuf/docs.rst b/pw_protobuf/docs.rst
index 11c5598..85370cd 100644
--- a/pw_protobuf/docs.rst
+++ b/pw_protobuf/docs.rst
@@ -856,13 +856,7 @@
 standard-library macros are suffixed with underscores to avoid compilation
 failures. This can be seen below in ``Channel.operator``, which is mapped to
 ``Channel::Message::operator_`` to avoid conflicting with the ``operator``
-keyword. Similarly, some POSIX signals are provided as macros by the
-``<csignal>`` header, so those names need to be suffixed with underscores in the
-generated code. Note, however, that some signal names are left unchanged. These
-signals aren't defined in the standard library, so they won't cause any problems
-unless the user defines custom macros for them; any naming conflicts caused by
-user-defined macros are the user's responsibility.
-(https://google.github.io/styleguide/cppguide.html#Preprocessor_Macros)
+keyword.
 
 .. code::
 
@@ -872,6 +866,25 @@
     Company operator = 3;
   }
 
+.. code:: c++
+
+  struct Channel::Message {
+    int32_t bitrate;
+    float signal_to_noise_ratio;
+    Company::Message operator_;
+  };
+
+Similarly, as shown in the example below, some POSIX-signal names conflict with
+macros defined by the standard-library header ``<csignal>`` and therefore
+require underscore suffixes in the generated code. Note, however, that some
+signal names are left alone. This is because ``<csignal>`` only defines a subset
+of the POSIX signals as macros; the rest are perfectly valid identifiers that
+won't cause any problems unless the user defines custom macros for them. Any
+naming conflicts caused by user-defined macros are the user's responsibility
+(https://google.github.io/styleguide/cppguide.html#Preprocessor_Macros).
+
+.. code::
+
   enum PosixSignal {
     NONE = 0;
     SIGHUP = 1;
@@ -890,12 +903,6 @@
 
 .. code:: c++
 
-  struct Channel::Message {
-    int32_t bitrate;
-    float signal_to_noise_ratio;
-    Company::Message operator_;
-  };
-
   enum class PosixSignal {
     NONE = 0,
     SIGHUP = 1,