clk: renesas: rzg2l: Use FIELD_GET() for PLL register fields

Use FIELD_GET() for PLL register fields.  This is its purpose.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230912045157.177966-14-claudiu.beznea.uj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Author: claudiubeznea

drivers/clk/renesas/rzg2l-cpg.c

@@ -11,6 +11,7 @@
  * Copyright (C) 2015 Renesas Electronics Corp.
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/clk/renesas.h>
@@ -38,14 +39,13 @@
 #define WARN_DEBUG(x)	do { } while (0)
 #endif
 
-#define DIV_RSMASK(v, s, m)	((v >> s) & m)
 #define GET_SHIFT(val)		((val >> 12) & 0xff)
 #define GET_WIDTH(val)		((val >> 8) & 0xf)
 
-#define KDIV(val)		DIV_RSMASK(val, 16, 0xffff)
-#define MDIV(val)		DIV_RSMASK(val, 6, 0x3ff)
-#define PDIV(val)		DIV_RSMASK(val, 0, 0x3f)
-#define SDIV(val)		DIV_RSMASK(val, 0, 0x7)
+#define KDIV(val)		FIELD_GET(GENMASK(31, 16), val)
+#define MDIV(val)		FIELD_GET(GENMASK(15, 6), val)
+#define PDIV(val)		FIELD_GET(GENMASK(5, 0), val)
+#define SDIV(val)		FIELD_GET(GENMASK(2, 0), val)
 
 #define CLK_ON_R(reg)		(reg)
 #define CLK_MON_R(reg)		(0x180 + (reg))