staging: wfx: fix spelling mistake "hexdecimal" -> "hexadecimal"

There is a spelling mistake in the documentation and a module parameter
description. Fix these.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20191008082205.19740-1-colin.king@canonical.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wfx/Documentation/devicetree/bindings/net/wireless/siliabs,wfx.txt

@@ -89,7 +89,7 @@ Some properties are recognized either by SPI and SDIO versions:
    this property, driver will disable most of power saving features.
  - config-file: Use an alternative file as PDS. Default is `wf200.pds`. Only
    necessary for development/debug purpose.
- - slk_key: String representing hexdecimal value of secure link key to use.
+ - slk_key: String representing hexadecimal value of secure link key to use.
    Must contains 64 hexadecimal digits. Not supported in current version.
 
 WFx driver also supports `mac-address` and `local-mac-address` as described in

drivers/staging/wfx/main.c

@@ -48,7 +48,7 @@ MODULE_PARM_DESC(gpio_wakeup, "gpio number for wakeup. -1 for none.");
 
 static char *slk_key;
 module_param(slk_key, charp, 0600);
-MODULE_PARM_DESC(slk_key, "secret key for secure link (expect 64 hexdecimal digits).");
+MODULE_PARM_DESC(slk_key, "secret key for secure link (expect 64 hexadecimal digits).");
 
 #define RATETAB_ENT(_rate, _rateid, _flags) { \
 	.bitrate  = (_rate),   \