mesa: Move is_power_of_two() function from brw_context.h to macros.h.

This makes the function available from core Mesa code, including the
GLSL compiler.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>

src/mesa/drivers/dri/i965/brw_context.h

@@ -1430,12 +1430,6 @@ struct brw_context
    struct intel_screen *intelScreen;
 };
 
-static inline bool
-is_power_of_two(uint32_t value)
-{
-   return (value & (value - 1)) == 0;
-}
-
 /*======================================================================
  * brw_vtbl.c
  */

src/mesa/main/macros.h

@@ -684,6 +684,17 @@ minify(unsigned value, unsigned levels)
     return MAX2(1, value >> levels);
 }
 
+/**
+ * Return true if the given value is a power of two.
+ *
+ * Note that this considers 0 a power of two.
+ */
+static inline bool
+is_power_of_two(unsigned value)
+{
+   return (value & (value - 1)) == 0;
+}
+
 /**
  * Align a value up to an alignment value
  *