x86, setup: reorganize the early console setup

Separate early_serial_console from tty.c

This allows for reuse of
early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/.

-v2: according to hpa, don't include string.c etc
-v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c
     for setup code

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4C568D2B.205@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/boot/cmdline.c

@@ -27,9 +27,8 @@ static inline int myisspace(u8 c)
  * Returns the length of the argument (regardless of if it was
  * truncated to fit in the buffer), or -1 on not found.
  */
-int cmdline_find_option(const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int len = -1;
@@ -100,9 +99,8 @@ int cmdline_find_option(const char *option, char *buffer, int bufsize)
  * Returns the position of that option (starts counting with 1)
  * or 0 on not found
  */
-int cmdline_find_option_bool(const char *option)
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int pos = 0, wstart = 0;