pw_log_zephyr: Make shell printf macros safe for use in if/else blocks

Usage of shell printf macros with tokenization within if/else
blocks that don't use braces causes compile error.

Change-Id: Ifde18a3ab1dcd98257250b11b0588d06395d6500
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/232031
Lint: Lint 🤖 <[email protected]>
Reviewed-by: Armando Montanez <[email protected]>
Commit-Queue: Al Semjonovs <[email protected]>

pw_log_zephyr/zephyr_public_overrides/zephyr_custom_shell.h

@@ -31,32 +31,32 @@
 #undef shell_error
 
 #define shell_fprintf(sh, color, fmt, ...) \
-  {                                        \
+  do {                                     \
     (void)(sh);                            \
     (void)(color);                         \
     PW_LOG_INFO(fmt, ##__VA_ARGS__);       \
-  }
+  } while (0)
 
 #define shell_info(_sh, _ft, ...)    \
-  {                                  \
+  do {                               \
     (void)(_sh);                     \
     PW_LOG_INFO(_ft, ##__VA_ARGS__); \
-  }
+  } while (0)
 
 #define shell_print(_sh, _ft, ...)   \
-  {                                  \
+  do {                               \
     (void)(_sh);                     \
     PW_LOG_INFO(_ft, ##__VA_ARGS__); \
-  }
+  } while (0)
 
 #define shell_warn(_sh, _ft, ...)    \
-  {                                  \
+  do {                               \
     (void)(_sh);                     \
     PW_LOG_WARN(_ft, ##__VA_ARGS__); \
-  }
+  } while (0)
 
 #define shell_error(_sh, _ft, ...)    \
-  {                                   \
+  do {                                \
     (void)(_sh);                      \
     PW_LOG_ERROR(_ft, ##__VA_ARGS__); \
-  }
+  } while (0)