kv_pair: Fix improper usage of calloc() in kv_pair_new()

Seems we've been lucky not to have had issues with this, until Stephen
Gilles (sgilles@math.umd.edu) encountered problems running fmap_decode
on an ARM-based system (Asus C201 / veyron_speedy) using musl libc.

TEST=unit tests pass, fmap_decode no longer crashes for Stephen

Signed-off-by: David Hendricks <dhendrix@chromium.org>
Change-Id: I27b2c7ee8476cb66d482632ca509265310996835
Reviewed-on: https://chromium-review.googlesource.com/366897
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
diff --git a/lib/kv_pair.c b/lib/kv_pair.c
index 2572c64..336ee4f 100644
--- a/lib/kv_pair.c
+++ b/lib/kv_pair.c
@@ -56,7 +56,7 @@
 	struct kv_pair *kv;
-	kv = calloc(0, sizeof(*kv));
+	kv = calloc(1, sizeof(*kv));
 	if (!kv)
 		return NULL;