AMREX_DEVICE_PRINTF: Host (#4116)

In AMReX, device means host if compiled for CPUs.
Add support for printf debugging on CPUs for `AMREX_DEVICE_PRINTF`.

Currently, the macro was undefined, unless for the special case of SYCL
compilation for host code paths where it worked.

Author: ax3l

Src/Base/AMReX_GpuPrint.H

@@ -2,8 +2,6 @@
 #define AMREX_GPU_PRINT_H_
 #include <AMReX_Config.H>
 
-#if !defined(__APPLE__)
-
 #include <cstdio>
 
 #ifdef AMREX_USE_SYCL
@@ -23,7 +21,9 @@
 #  define AMREX_DEVICE_PRINTF(...) std::printf(__VA_ARGS__);
 #elif defined(AMREX_USE_HIP)
 #  define AMREX_DEVICE_PRINTF(...) ::printf(__VA_ARGS__);
+#else
+#  define AMREX_DEVICE_PRINTF(format,...) { \
+      std::printf(format, __VA_ARGS__); }
 #endif
 
-#endif  // !defined(__APPLE__)
 #endif  // AMREX_GPU_PRINT_H_