afboot-stm32: remove patch, doesn't apply

package/afboot-stm32/patches/patch-Makefile

@@ -1,23 +0,0 @@
---- afboot-stm32-8e9e03159ce47629d40dbed4c50c1879b69bb197.orig/Makefile	2017-01-19 06:54:21.000000000 +0100
-+++ afboot-stm32-8e9e03159ce47629d40dbed4c50c1879b69bb197/Makefile	2017-01-19 06:55:03.370200767 +0100
-@@ -1,14 +1,15 @@
- CROSS_COMPILE ?= arm-none-eabi-
- 
--CC = $(CROSS_COMPILE)gcc
--LD = $(CROSS_COMPILE)ld
--OBJCOPY = $(CROSS_COMPILE)objcopy
--OBJDUMP = $(CROSS_COMPILE)objdump
-+CC ?= $(CROSS_COMPILE)gcc
-+LD ?= $(CROSS_COMPILE)ld
-+OBJCOPY ?= $(CROSS_COMPILE)objcopy
-+OBJDUMP ?= $(CROSS_COMPILE)objdump
- SIZE = $(CROSS_COMPILE)size
- GDB = $(CROSS_COMPILE)gdb
- OPENOCD = openocd
- 
--CFLAGS := -mthumb -mcpu=cortex-m4
-+CFLAGS ?= 
-+CFLAGS += -mthumb
- CFLAGS += -ffunction-sections -fdata-sections
- CFLAGS += -Os -std=gnu99 -Wall
- LINKERFLAGS := -nostartfiles --gc-sections