fpga: dfl: afu: add DFL_FPGA_GET_API_VERSION/CHECK_EXTENSION ioctls support

DFL_FPGA_GET_API_VERSION and DFL_FPGA_CHECK_EXTENSION ioctls are common
ones which need to be supported by all feature devices drivers including
FME and AFU. This patch implements above 2 ioctls in FPGA Accelerated
Function Unit (AFU) driver.

Signed-off-by: Tim Whisonant <tim.whisonant@intel.com>
Signed-off-by: Enno Luebbers <enno.luebbers@intel.com>
Signed-off-by: Shiva Rao <shiva.rao@intel.com>
Signed-off-by: Christopher Rauer <christopher.rauer@intel.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/fpga/dfl-afu-main.c

@@ -236,6 +236,13 @@ static int afu_release(struct inode *inode, struct file *filp)
 	return 0;
 }
 
+static long afu_ioctl_check_extension(struct dfl_feature_platform_data *pdata,
+				      unsigned long arg)
+{
+	/* No extension support for now */
+	return 0;
+}
+
 static long afu_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct platform_device *pdev = filp->private_data;
@@ -248,6 +255,10 @@ static long afu_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	pdata = dev_get_platdata(&pdev->dev);
 
 	switch (cmd) {
+	case DFL_FPGA_GET_API_VERSION:
+		return DFL_FPGA_API_VERSION;
+	case DFL_FPGA_CHECK_EXTENSION:
+		return afu_ioctl_check_extension(pdata, arg);
 	default:
 		/*
 		 * Let sub-feature's ioctl function to handle the cmd