Indent #ifdef blocks, improve comment for MSVC pragma.

PiperOrigin-RevId: 451614625
Change-Id: I5b46572521955b51da48f183d2195817df6ea28d

src/engine/engine_io.c

@@ -42,7 +42,7 @@
 #endif
 
 #ifdef _MSC_VER
-#pragma warning (disable: 4305)  // tell MSVC to not complain that float x = 0.1 should be 0.1f
+  #pragma warning (disable: 4305)  // disable MSVC warning: truncation from 'double' to 'float'
 #endif
 
 #define PTRDIFF(x, y) ((void*)(x) - (void*)(y))

src/engine/engine_vis_init.c

@@ -25,7 +25,7 @@
 #include "engine/engine_util_misc.h"
 
 #ifdef _MSC_VER
-#pragma warning (disable: 4305) // tell MSVC to not complain that float x = 0.1 should be 0.1f
+  #pragma warning (disable: 4305)  // disable MSVC warning: truncation from 'double' to 'float'
 #endif