[Keyboard] Add zvecr/zv48 (#9227)

* Add zv48 keyboard

* tidy up rules

* correct product name

keyboards/zvecr/zv48/f411/rules.mk

@@ -0,0 +1,27 @@
+## chip/board settings
+# the next two should match the directories in
+#  <chibios>/os/hal/ports/$(MCU_FAMILY)/$(MCU_SERIES)
+MCU_FAMILY = STM32
+MCU_SERIES = STM32F4xx
+# linker script to use
+# it should exist either in <chibios>/os/common/ports/ARMCMx/compilers/GCC/ld/
+#  or <this_dir>/ld/
+MCU_LDSCRIPT = STM32F411xE
+# startup code to use
+# is should exist in <chibios>/os/common/ports/ARMCMx/compilers/GCC/mk/
+MCU_STARTUP = stm32f4xx
+# it should exist either in <chibios>/os/hal/boards/
+#  or <this_dir>/boards
+BOARD = BLACKPILL_STM32_F411
+# Cortex version
+# Teensy LC is cortex-m0; Teensy 3.x are cortex-m4
+MCU  = cortex-m4
+# ARM version, CORTEX-M0/M1 are 6, CORTEX-M3/M4/M7 are 7
+ARMV = 7
+USE_FPU = yes
+# Address of the booloader in system memory
+STM32_BOOTLOADER_ADDRESS = 0x1FFF0000
+
+# Options to pass to dfu-util when flashing
+DFU_ARGS = -d 0483:df11 -a 0 -s 0x08000000:leave
+DFU_SUFFIX_ARGS = -v 0483 -p df11