pm_runtime: add runtime power management initial implementation

This patch adds initial empty implementation of runtime power management.
It is based on linux kernel implementation and will be developed
in the future.

Signed-off-by: Tomasz Lauda <tomasz.lauda@linux.intel.com>
diff --git a/doc/sof_uapi.doxygen.in b/doc/sof_uapi.doxygen.in
index 74052f1..18444c9 100644
--- a/doc/sof_uapi.doxygen.in
+++ b/doc/sof_uapi.doxygen.in
@@ -6,7 +6,8 @@
 GENERATE_XML	 = YES
 
 CASE_SENSE_NAMES = NO
-INPUT            = @top_srcdir@/src/include/uapi
+INPUT            = @top_srcdir@/src/include/uapi \
+                   @top_srcdir@/src/include/sof
 EXCLUDE		 =
 RECURSIVE	 = YES
 FILE_PATTERNS    = *.c *.h