cmake: bump version to 3.1.2

- Bump version to 3.1.2
- Add a hash file

Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/cmake/cmake.hash

@@ -0,0 +1,2 @@
+# Locally calculated
+sha256  2b210f7d867a1e716c1895357ebe63c7b9ae61fdb5f2d300ab2f01795f085b35  cmake-3.1.2.tar.gz

package/cmake/cmake.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-CMAKE_VERSION_MAJOR = 3.0
+CMAKE_VERSION_MAJOR = 3.1
 CMAKE_VERSION = $(CMAKE_VERSION_MAJOR).2
 CMAKE_SITE = http://www.cmake.org/files/v$(CMAKE_VERSION_MAJOR)
 CMAKE_LICENSE = BSD-3c