execline: fix hash "sha" type spelling

sah256 -> sha256

Fixes:
http://autobuild.buildroot.net/results/9d0/9d054a26d7833353efbe49c984a7cb66d77b1d0c/

Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/execline/execline.hash

@@ -1,3 +1,3 @@
 # Locally generated
 sha256 e4bb8fc8f20cca96f4bac9f0f74ebce5081b4b687bb11c79c843faf12507a64b  execline-2.3.0.4.tar.gz
-sah256 6ee77e7199d69b707ab864ea7a838f9562717aaa41c89413bdb2cf835f95052f  COPYING
+sha256 6ee77e7199d69b707ab864ea7a838f9562717aaa41c89413bdb2cf835f95052f  COPYING