lib: create common ascii hex array

Add a common hex array in hexdump.c so everyone can use it.

Add a common hi/lo helper to avoid the shifting masking that is
done to get the upper and lower nibbles of a byte value.

Pull the pack_hex_byte helper from kgdb as it is opencoded many
places in the tree that will be consolidated.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/pnp/support.c b/drivers/pnp/support.c
index 3eba85e..95b076c 100644
--- a/drivers/pnp/support.c
+++ b/drivers/pnp/support.c
@@ -45,10 +45,10 @@
 	str[0] = 'A' + ((id >> 26) & 0x3f) - 1;
 	str[1] = 'A' + ((id >> 21) & 0x1f) - 1;
 	str[2] = 'A' + ((id >> 16) & 0x1f) - 1;
-	str[3] = hex_asc((id >> 12) & 0xf);
-	str[4] = hex_asc((id >>  8) & 0xf);
-	str[5] = hex_asc((id >>  4) & 0xf);
-	str[6] = hex_asc((id >>  0) & 0xf);
+	str[3] = hex_asc_hi(id >> 8);
+	str[4] = hex_asc_lo(id >> 8);
+	str[5] = hex_asc_hi(id);
+	str[6] = hex_asc_lo(id);
 	str[7] = '\0';
 }