musl: bump to version 1.1.15

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/musl/musl.hash

@@ -1,2 +1,2 @@
 # Locally calculated after checking pgp signature
-sha256	35f6c00c84a6091bd5dab29eedde7508dae755ead92dcc0239f3677d1055b9b5  musl-1.1.14.tar.gz
+sha256	97e447c7ee2a7f613186ec54a93054fe15469fe34d7d323080f7ef38f5ecb0fa  musl-1.1.15.tar.gz

package/musl/musl.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-MUSL_VERSION = 1.1.14
+MUSL_VERSION = 1.1.15
 MUSL_SITE = http://www.musl-libc.org/releases
 MUSL_LICENSE = MIT
 MUSL_LICENSE_FILES = COPYRIGHT