spi: mxc_spi: fix warnings if CLK_ENABLED not set

Following warnings (unused variables) are raised:

drivers/spi/mxc_spi.c: In function 'mxc_spi_probe':
drivers/spi/mxc_spi.c:595:14: error: unused variable 'blob' [-Werror=unused-variable]
595 |  const void *blob = gd->fdt_blob;
    |              ^~~~
drivers/spi/mxc_spi.c:594:6: error: unused variable 'node' [-Werror=unused-variable]
594 |  int node = dev_of_offset(bus);

Move the variable declaration inside the code where they are used.

Signed-off-by: Stefano Babic <sbabic@denx.de>

drivers/spi/mxc_spi.c

@@ -591,8 +591,6 @@ void spi_release_bus(struct spi_slave *slave)
 static int mxc_spi_probe(struct udevice *bus)
 {
 	struct mxc_spi_slave *mxcs = dev_get_plat(bus);
-	int node = dev_of_offset(bus);
-	const void *blob = gd->fdt_blob;
 	int ret;
 	int i;
 
@@ -629,6 +627,8 @@ static int mxc_spi_probe(struct udevice *bus)
 
 	mxcs->max_hz = clk_get_rate(&clk);
 #else
+	int node = dev_of_offset(bus);
+	const void *blob = gd->fdt_blob;
 	mxcs->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency",
 				      20000000);
 #endif