subprojects: fix wraps

Fixed the missing two wrap files; also simplified meson deps via
`[provide]`.

1. libgpiod; installed from WrapDB; reference:
[1] https://mesonbuild.com/Wrapdb-projects.html
This is also alligned with Yocto; reference:
[1] https://github.com/openbmc/openbmc/blob/78b727985e7571e0b196561e44427690f04d57d9/meta-openembedded/meta-oe/recipes-support/libgpiod/libgpiod_1.6.3.bb
2. sdbusplus

Tested: builds on systems without the two dependencies where meson
automatically downloads them

Signed-off-by: Nan Zhou <nanzhoumails@gmail.com>
Change-Id: I81305c3f399fbe437cc8e32015e074eff93078bc
diff --git a/subprojects/sdbusplus.wrap b/subprojects/sdbusplus.wrap
new file mode 100644
index 0000000..7b076d0
--- /dev/null
+++ b/subprojects/sdbusplus.wrap
@@ -0,0 +1,6 @@
+[wrap-git]
+url = https://github.com/openbmc/sdbusplus.git
+revision = HEAD
+
+[provide]
+sdbusplus = sdbusplus_dep