Documentation: fpga: dfl: change FPGA indirect article to an

Change use of 'a fpga' to 'an fpga'
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20210608212350.3029742-4-trix@redhat.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/fpga/dfl.rst

@@ -57,7 +57,7 @@ FPGA Interface Unit (FIU) represents a standalone functional unit for the
 interface to FPGA, e.g. the FPGA Management Engine (FME) and Port (more
 descriptions on FME and Port in later sections).
 
-Accelerated Function Unit (AFU) represents a FPGA programmable region and
+Accelerated Function Unit (AFU) represents an FPGA programmable region and
 always connects to a FIU (e.g. a Port) as its child as illustrated above.
 
 Private Features represent sub features of the FIU and AFU. They could be
@@ -311,7 +311,7 @@ The driver organization in virtualization case is illustrated below:
              | PCI PF Device |            |          | PCI VF Device |
              +---------------+            |          +---------------+
 
-FPGA PCIe device driver is always loaded first once a FPGA PCIe PF or VF device
+FPGA PCIe device driver is always loaded first once an FPGA PCIe PF or VF device
 is detected. It:
 
 * Finishes enumeration on both FPGA PCIe PF and VF device using common