thunderbolt: Improve USB4 config symbol help text

Fix the spelling of "specification", and add a missing "the" article.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

drivers/thunderbolt/Kconfig

@@ -8,8 +8,8 @@ menuconfig USB4
 	select CRYPTO_HASH
 	select NVMEM
 	help
-	  USB4 and Thunderbolt driver. USB4 is the public speficiation
-	  based on Thunderbolt 3 protocol. This driver is required if
+	  USB4 and Thunderbolt driver. USB4 is the public specification
+	  based on the Thunderbolt 3 protocol. This driver is required if
 	  you want to hotplug Thunderbolt and USB4 compliant devices on
 	  Apple hardware or on PCs with Intel Falcon Ridge or newer.