I solved problem.

I had to modify Makefile and compile it on destination system (BananaPi).

In Makefile, I changed

from (line 52)
CONFIG_PLATFORM_I386_PC = y
to

CONFIG_PLATFORM_I386_PC = n

from (line 82)
CONFIG_PLATFORM_ARM_SUNxI = n
to

CONFIG_PLATFORM_ARM_SUNxI = y

FROM (lines from 943 to 949)

ifeq ($(CONFIG_PLATFORM_ARM_SUNxI), y)
EXTRA_CFLAGS += -DCONFIG_LITTLE_ENDIAN -DCONFIG_PLATFORM_ARM_SUNxI
ARCH := arm
CROSS_COMPILE := arm-none-linux-gnueabi-
KVER := 3.0.8
#KSRC:= ../lichee/linux-3.0/
endif

TO

ifeq ($(CONFIG_PLATFORM_ARM_SUNxI), y)
#EXTRA_CFLAGS += -DCONFIG_LITTLE_ENDIAN -DCONFIG_PLATFORM_ARM_SUNxI
EXTRA_CFLAGS += -DCONFIG_LITTLE_ENDIAN
#ARCH := arm
#CROSS_COMPILE := arm-none-linux-gnueabi-
KVER := 3.16.0-4-armmp-lpae
KSRC:= /usr/src/linux-headers-3.16.0-4-armmp-lpae

endif

Variable KVER:
put here result of "uname -r"

Variable KSRC:
put here path to current running kernel source code.

Variable ARCH and CROSS_COMPILE - Commented out, because it's not cross compilation.
Option "-DCONFIG_PLATFORM_ARM_SUNxI", removed. Probably needed by cross compilation. I didn't check it.

Since few days, WiFi card work without problems.

from rtl8812au.