Migrate noblur library complication to Bazel

This adds a new target //cpp/linux-specific:noblur64 which automatically
compiles a shared library using Bazel. This target replaces old
//cpp:noblur64.

Unfortunately setting up 32-bit toolchain for Bazel is not trivial, so
this commit doesn't implement target that replaces //cpp:noblur.
However, it should be safe given these libraries are already kept
prebuilt in cpp/prebuilt/ and haven't been updated for 4 years.

Author: p0deje

cpp/build.desc

@@ -0,0 +1,16 @@
+cc_binary(
+    name = "noblur64",
+    srcs = glob([
+        "*.c",
+        "*.h",
+    ]),
+    copts = [
+        "-Wall",
+        "-shared",
+        "-fPIC",
+        "-Os",
+        "-fshort-wchar",
+        "-m64",
+    ],
+    linkshared = True,
+)