accel: Document generic accelerator headers

These headers are meant to be include by any file to check
the availability of accelerators, thus are not accelerator
specific.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230624174121.11508-3-philmd@linaro.org>

include/sysemu/hax.h

@@ -19,6 +19,8 @@
  *
  */
 
+/* header to be included in non-HAX-specific code */
+
 #ifndef QEMU_HAX_H
 #define QEMU_HAX_H
 

include/sysemu/kvm.h

@@ -11,6 +11,8 @@
  *
  */
 
+/* header to be included in non-KVM-specific code */
+
 #ifndef QEMU_KVM_H
 #define QEMU_KVM_H
 

include/sysemu/nvmm.h

@@ -7,6 +7,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-NVMM-specific code */
+
 #ifndef QEMU_NVMM_H
 #define QEMU_NVMM_H
 

include/sysemu/tcg.h

@@ -5,6 +5,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-TCG-specific code */
+
 #ifndef SYSEMU_TCG_H
 #define SYSEMU_TCG_H
 

include/sysemu/whpx.h

@@ -10,6 +10,8 @@
  *
  */
 
+/* header to be included in non-WHPX-specific code */
+
 #ifndef QEMU_WHPX_H
 #define QEMU_WHPX_H
 

include/sysemu/xen.h

@@ -5,6 +5,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+/* header to be included in non-Xen-specific code */
+
 #ifndef SYSEMU_XEN_H
 #define SYSEMU_XEN_H