qtnfmac: drop -D__CHECK_ENDIAN from cflags

Flag -D__CHECK_ENDIAN was wrong: it should be -D__CHECK_ENDIAN__ instead.
However now this flag is enabled by default, so it can be removed.

Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/quantenna/qtnfmac/Makefile

@@ -25,7 +25,3 @@ qtnfmac_pearl_pcie-objs += \
 	pearl/pcie.o
 
 qtnfmac_pearl_pcie-$(CONFIG_DEBUG_FS) += debug.o
-
-#
-
-ccflags-y += -D__CHECK_ENDIAN