TYPO: put_char -> putchar

Booting/linux-bootstrap-2.md

@@ -254,7 +254,7 @@ void __attribute__((section(".inittext"))) putchar(int ch)
 
 `__attribute__((section(".inittext")))` means that this code will be in the `.inittext` section. We can find it in the linker file [setup.ld](https://github.com/torvalds/linux/blob/master/arch/x86/boot/setup.ld#L19).
 
-First of all, `put_char` checks for the `\n` symbol and if it is found, prints `\r` before. After that it outputs the character on the VGA screen by calling the BIOS with the `0x10` interrupt call:
+First of all, `putchar` checks for the `\n` symbol and if it is found, prints `\r` before. After that it outputs the character on the VGA screen by calling the BIOS with the `0x10` interrupt call:
 
 ```C
 static void __attribute__((section(".inittext"))) bios_putchar(int ch)