Add a new pldm verbosity option

- The intent behind this commit is to add a new
  compile time meson option to control the pldm verbosity.

- The value that is given for meson option goes into the
  default systemd environment file which is picked by the
  pldmd service unit before it starts.

- As the pldmd consumes the default pldmd file at runtime,
  we should be able to alter the verbosity by changing the
  content in /etc/default/pldm_verbosity file.

Tested By:
1. meson buildir
   check the pldmd file (make sure verbosity is 0 by default)
2. meson builddir -Dverbosity=1
   check the generated pldm_verbosity file (make sure verbosity is 1)
3. Flash the image & check if the pldm is loaded with the right verbosity
   that is set during compilation.
4. Change the verbosity in the /etc/default/pldm_verbosity file & restart
   pldmd.service, and check if the daemon picks up the change.

Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
Change-Id: Ica5607b801143b2806d343e3b82b043f078fcd22
diff --git a/meson_options.txt b/meson_options.txt
index 636d8cd..e1f6d43 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -1,4 +1,5 @@
 option('tests', type: 'feature', description: 'Build tests', value: 'enabled')
+option('verbosity',type:'integer',min:0, max:1, description: 'Enables/Disables pldm verbosity',value: 0)
 option('oe-sdk', type: 'feature', description: 'Enable OE SDK')
 option('oem-ibm', type: 'feature', description: 'Enable IBM OEM PLDM')
 option('requester-api', type: 'feature', description: 'Enable libpldm requester API', value: 'enabled')