pnpacpi: fix incorrect TEST_ALPHA() test

TEST_ALPHA() is broken and always returns 0.

[akpm@linux-foundation.org: return false for '@' as well, per Bjorn]
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index ec8e914..767f526 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -58,7 +58,7 @@
 	if (!(('0' <= (c) && (c) <= '9') || ('A' <= (c) && (c) <= 'F'))) \
 		return 0
 #define TEST_ALPHA(c) \
-	if (!('@' <= (c) || (c) <= 'Z')) \
+	if (!('A' <= (c) && (c) <= 'Z')) \
 		return 0
 static int __init ispnpidacpi(const char *id)
 {