meson: add basic meson

Since we don't have a CI for standard Make repositories anymore,
this repository has no CI.  Begin a simple meson conversion to
enable some CI for the bare minimum aspects of the repository still
being used in openbmc/openbmc.

    - libopenbmc_intf
    - op-pwrctl
    - pgood_wait
    - op-hostctl

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I598e91c08b5ad607b68c18bfa9a870603df19397
diff --git a/.gitignore b/.gitignore
index a76f2a3..54f1cfb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
+/build*/
+/subprojects/*
+!/subprojects/*.wrap
+
 *.exe
 *.o
 *.so