seq_buf: Don't use "proxy" headers

Update header inclusions to follow IWYU (Include What You Use)
principle.

Link: https://lkml.kernel.org/r/20240215142255.400264-1-andriy.shevchenko@linux.intel.com

Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

include/linux/seq_buf.h

@@ -2,7 +2,10 @@
 #ifndef _LINUX_SEQ_BUF_H
 #define _LINUX_SEQ_BUF_H
 
-#include <linux/fs.h>
+#include <linux/bug.h>
+#include <linux/minmax.h>
+#include <linux/seq_file.h>
+#include <linux/types.h>
 
 /*
  * Trace sequences are used to allow a function to call several other functions

lib/seq_buf.c

@@ -13,9 +13,19 @@
  * seq_buf_init() more than once to reset the seq_buf to start
  * from scratch.
  */
-#include <linux/uaccess.h>
-#include <linux/seq_file.h>
+
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/hex.h>
+#include <linux/minmax.h>
+#include <linux/printk.h>
 #include <linux/seq_buf.h>
+#include <linux/seq_file.h>
+#include <linux/sprintf.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
 
 /**
  * seq_buf_can_fit - can the new data fit in the current buffer?