math.h: Introduce data types for fractional numbers

Introduce a macro to produce data types like

	struct TYPE_fract {
		__TYPE numerator;
		__TYPE denominator;
	};

to be used in the code wherever it's needed.

In the following changes convert some users to it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220126135353.24007-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

include/linux/math.h

@@ -2,6 +2,7 @@
 #ifndef _LINUX_MATH_H
 #define _LINUX_MATH_H
 
+#include <linux/types.h>
 #include <asm/div64.h>
 #include <uapi/linux/kernel.h>
 
@@ -106,6 +107,17 @@
 }							\
 )
 
+#define __STRUCT_FRACT(type)				\
+struct type##_fract {					\
+	__##type numerator;				\
+	__##type denominator;				\
+};
+__STRUCT_FRACT(s16)
+__STRUCT_FRACT(u16)
+__STRUCT_FRACT(s32)
+__STRUCT_FRACT(u32)
+#undef __STRUCT_FRACT
+
 /*
  * Multiplies an integer by a fraction, while avoiding unnecessary
  * overflow or loss of precision.