make: add missing header files and update build system

include/shell/buzzer.h

@@ -0,0 +1,3 @@
+#pragma once
+
+int shell_buzzer(struct console *con, size_t argc, const char **argv);

include/shell/rtc.h

@@ -5,3 +5,4 @@ struct console;
 int shell_date(struct console *con, size_t argc, const char **argv);
 int shell_time(struct console *con, size_t argc, const char **argv);
 int shell_set_date(struct console *con, size_t argc, const char **argv);
+int shell_set_time(struct console *con, size_t argc, const char **argv);

source/platform/stm32f0/Makefile

@@ -2,6 +2,7 @@ obj-y += source/platform/spi_flash.o
 obj-y += source/platform/usart.o
 
 obj-y += source/platform/stm32f0/alarm.o
+obj-y += source/platform/stm32f0/buzzer.o
 obj-y += source/platform/stm32f0/gpio.o
 obj-y += source/platform/stm32f0/rcc.o
 obj-y += source/platform/stm32f0/rtc.o

source/platform/stm32f1/Makefile

@@ -2,6 +2,7 @@ obj-y += source/platform/spi_flash.o
 obj-y += source/platform/usart.o
 
 obj-y += source/platform/stm32f1/alarm.o
+obj-y += source/platform/stm32f1/buzzer.o
 obj-y += source/platform/stm32f1/gpio.o
 obj-y += source/platform/stm32f1/rcc.o
 obj-y += source/platform/stm32f1/rtc.o

source/shell/Makefile

@@ -1,5 +1,6 @@
 obj-y += source/shell/args.o
 obj-y += source/shell/boot.o
+obj-y += source/shell/buzzer.o
 obj-y += source/shell/cmd.o
 obj-y += source/shell/echo.o
 obj-y += source/shell/flash.o