smartmontools: Update to 7.0

Removed weird uclibc++ compatibility stuff as it seems to not be needed
anymore.

Switched to standard variables.

Added PKG_BUILD_PARALLEL for faster compilation.

Removed PKG_FIXUP as it seems the package has been fixed already.

A few changes to the CFLAGS and linker options resulted in ipk size going
from 244694 to 244283, possibly due to previous overlinking.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

utils/smartmontools/patches/001-musl-compat-realpath.patch

@@ -1,19 +0,0 @@
-commit 2473c5e01ea14fae96c157d8bce3a3ec1da124f3
-Author: Maxim Storchak <m.storchak@gmail.com>
-Date:   Sat Dec 9 15:21:51 2017 +0200
-
-    Replace canonicalize_file_name with realpath equivalent
-
-diff --git a/os_linux.cpp b/os_linux.cpp
-index 134d5bc..0575a13 100644
---- a/os_linux.cpp
-+++ b/os_linux.cpp
-@@ -3176,7 +3176,7 @@ static bool is_hpsa(const char * name)
- {
-   char path[128];
-   snprintf(path, sizeof(path), "/sys/block/%s/device", name);
--  char * syshostpath = canonicalize_file_name(path);
-+  char * syshostpath = realpath(path, NULL);
-   if (!syshostpath)
-     return false;
-