libpayload: increase MAX_ARGC_COUNT

MAX_ARGC_COUNT limits the payload to ten parameters which is not
enough when used with a proprietary first stage bootloader providing
hardware description using around 20 parameters.

This patch makes the libpayload able to get up to 32 parameters.

Change-Id: I49925040d951dffb9c11425334674d8d498821f2
Signed-off-by: Jeremy Compostella <jeremy.compostella@gmail.com>
Reviewed-on: https://review.coreboot.org/17467
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: Martin Roth <martinroth@google.com>
Reviewed-by: Nico Huber <nico.h@gmx.de>

payloads/libpayload/include/libpayload.h

@@ -78,7 +78,7 @@ static inline u32 div_round_up(u32 n, u32 d) { return (n + d - 1) / d; }
 
 #define RAND_MAX 0x7fffffff
 
-#define MAX_ARGC_COUNT 10
+#define MAX_ARGC_COUNT 32
 
 /*
  * Payload information parameters - these are used to pass information