staging: comedi: amplc_pci224: convert CLK_CONFIG() macro to function

Convert the `CLK_CLKFIG(chan, src)` macro to a static function
`pci224_clk_config(chan, src)`.  This is consistent with an earlier
change to convert `GAT_CONFIG(chan, src)` to a static function.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/amplc_pci224.c

@@ -206,8 +206,11 @@
 #define CLK_1KHZ	5	/* internal 1 kHz clock */
 #define CLK_OUTNM1	6	/* output of channel-1 modulo total */
 #define CLK_EXT		7	/* external clock */
-/* Macro to construct clock input configuration register value. */
-#define CLK_CONFIG(chan, src)	((((chan) & 3) << 3) | ((src) & 7))
+
+static unsigned int pci224_clk_config(unsigned int chan, unsigned int src)
+{
+	return ((chan & 3) << 3) | (src & 7);
+}
 
 /*
  * Counter/timer gate input configuration sources.
@@ -825,9 +828,11 @@ static void pci224_ao_start_pacer(struct comedi_device *dev,
 	/* Make sure Z2-2 is gated on.  */
 	outb(pci224_gat_config(2, GAT_VCC), devpriv->iobase1 + PCI224_ZGAT_SCE);
 	/* Z2-2 needs 10 MHz clock. */
-	outb(CLK_CONFIG(2, CLK_10MHZ), devpriv->iobase1 + PCI224_ZCLK_SCE);
+	outb(pci224_clk_config(2, CLK_10MHZ),
+	     devpriv->iobase1 + PCI224_ZCLK_SCE);
 	/* Z2-0 is clocked from Z2-2's output. */
-	outb(CLK_CONFIG(0, CLK_OUTNM1), devpriv->iobase1 + PCI224_ZCLK_SCE);
+	outb(pci224_clk_config(0, CLK_OUTNM1),
+	     devpriv->iobase1 + PCI224_ZCLK_SCE);
 
 	comedi_8254_pacer_enable(dev->pacer, 2, 0, false);
 }