[uaccess] Remove redundant copy_from_user() and copy_to_user()

Remove the now-redundant copy_from_user() and copy_to_user() wrapper
functions.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/interface/efi/efi_bofm.c

@@ -23,6 +23,7 @@
 
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
+#include <string.h>
 #include <errno.h>
 #include <ipxe/bofm.h>
 #include <ipxe/efi/efi.h>

src/interface/efi/efi_cmdline.c

@@ -31,6 +31,7 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <ctype.h>
 #include <errno.h>
 #include <ipxe/init.h>

src/interface/efi/efi_pci.c

@@ -24,6 +24,7 @@
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdlib.h>
+#include <string.h>
 #include <errno.h>
 #include <ipxe/pci.h>
 #include <ipxe/acpi.h>

src/interface/xen/xenbus.c

@@ -24,6 +24,7 @@
 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdio.h>
+#include <string.h>
 #include <errno.h>
 #include <ipxe/malloc.h>
 #include <ipxe/device.h>