include: math: doc: add doxygen groups

add doxygen groups to include/zephyr/math header files and fold them
under Utilities top-level group.

Signed-off-by: Benjamin Cabé <[email protected]>

Author: kartben

include/zephyr/math/ilog2.h

@@ -18,6 +18,13 @@
  * @brief Provide ilog2() function
  */
 
+/**
+ * @defgroup math_ilog2 Math Ilog2 Functions
+ * @ingroup utilities
+ * @brief Integer log2 utilities for mathematical operations
+ * @{
+ */
+
 /**
  *
  * @brief Calculate the floor of log2 for compile time constant
@@ -97,4 +104,8 @@
 		find_msb_set(n) - 1			\
 	)
 
+/**
+ * @}
+ */
+
 #endif /* ZEPHYR_INCLUDE_MATH_ILOG2_H_ */

include/zephyr/math/interpolation.h

@@ -19,6 +19,13 @@ extern "C" {
  * @brief Provide linear interpolation functions
  */
 
+/**
+ * @defgroup math_interpolation Math Interpolation Functions
+ * @ingroup utilities
+ * @brief Linear interpolation utilities for mathematical operations
+ * @{
+ */
+
 /**
  * @brief Perform a linear interpolation across an arbitrary curve
  *
@@ -68,6 +75,10 @@ static inline int32_t linear_interpolate(const int32_t *x_axis, const int32_t *y
 	return roundf(y_axis[idx_low] + (slope * x_shifted));
 }
 
+/**
+ * @}
+ */
+
 #ifdef __cplusplus
 }
 #endif