clk: at91: Convert to common field_{get,prep}() helpers

Drop the driver-specific field_get() and field_prep() macros, in favor
of the globally available variants from <linux/bitfield.h>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>

drivers/clk/at91/clk-peripheral.c

@@ -3,6 +3,7 @@
  *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
  */
 
+#include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/clk-provider.h>
 #include <linux/clkdev.h>

drivers/clk/at91/pmc.h

@@ -117,11 +117,6 @@ struct at91_clk_pms {
 	unsigned int parent;
 };
 
-#undef field_get
-#define field_get(_mask, _reg) (((_reg) & (_mask)) >> (ffs(_mask) - 1))
-#undef field_prep
-#define field_prep(_mask, _val) (((_val) << (ffs(_mask) - 1)) & (_mask))
-
 #define ndck(a, s) (a[s - 1].id + 1)
 #define nck(a) (a[ARRAY_SIZE(a) - 1].id + 1)