soc: riscv: riscv-privilege: andes_v5: make smu.h self contained

The header was not self-contained: it uses DT and utility macros but
<devicetree.h> and <sys/util_macro.h> were not included.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

soc/riscv/riscv-privilege/andes_v5/smu.h

@@ -11,6 +11,9 @@
 #ifndef SOC_RISCV_ANDES_V5_SMU_H_
 #define SOC_RISCV_ANDES_V5_SMU_H_
 
+#include <devicetree.h>
+#include <sys/util_macro.h>
+
 /*
  * SMU Register Base Address
  */