payloads: Drop unneeded empty lines

Change-Id: I6faeb7c783052edc4217d2d301dbb905e1fc6a19
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44605
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>

payloads/libpayload/libc/string.c

@@ -521,7 +521,6 @@ unsigned long int strtoul(const char *ptr, char **endptr, int base)
 	return val;
 }
 
-
 /**
  * Determine the number of leading characters in s that match characters in a
  * @param s A pointer to the string to analyse