Use api.hpp instead of api.h

Since the api.h file has been gradually deprecated, this submission
will use api.hpp instead of api.h

Change-Id: Ic9c8ebe0ba96b0a11b9415cd52acdf58fe9d828e
Signed-off-by: George Liu <liuxiwei@ieisystem.com>
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/ipmi/manual_messages.hpp b/ipmi/manual_messages.hpp
index 5418d60..86edd31 100644
--- a/ipmi/manual_messages.hpp
+++ b/ipmi/manual_messages.hpp
@@ -2,9 +2,7 @@
 
 #include <cstdint>
 
-namespace pid_control
-{
-namespace ipmi
+namespace pid_control::ipmi
 {
 
 enum ManualSubCmd
@@ -27,5 +25,4 @@
     uint8_t value;
 } __attribute__((packed));
 
-} // namespace ipmi
-} // namespace pid_control
+} // namespace pid_control::ipmi