misc: pci_endpoint_test: Drop initial kernel-doc marker

misc: pci_endpoint_test: Drop initial kernel-doc marker

This beginning comment is not kernel-doc, so change the "/**" to a
normal "/*" comment to prevent a kernel-doc warning:

  drivers/misc/pci_endpoint_test.c:3: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst

Link: https://lore.kernel.org/r/20230113063937.20912-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Krzysztof Wilczyński <kw@linux.com>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Kishon Vijay Abraham I <kishon@kernel.org>
Cc: linux-pci@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>