[202012] Added libpci and pciutils to the pmon docker (#12684) (#14056)

#### Why I did it

This is part of a corresponding change to the pcie daemon that enables it to verify PCI peripherals on a platform against a preconfigured YAML file, and enables the pcied daemon to call the system commands needed for PCI peripheral verification

#### How I did it
Adding aforementioned libraries to the Dockerfile.j2 file

#### How to verify it
run 'which setpci' from the pmon docker - would show the path of the binary

#### Description for the changelog

Modified pmon's Dockerfile.j2 to include pciutils and libpci libraries.

**cherry-pick of SHA: 7de04504c9518d68aa00c304b7376fdff4e1d318**

dockers/docker-platform-monitor/Dockerfile.j2

@@ -26,7 +26,8 @@ RUN apt-get update &&   \
         i2c-tools       \
         psmisc          \
         python3-jsonschema \
-        libpci3
+        libpci3         \
+        pciutils
 
 # TODO: Remove these lines once we no longer need Python 2
 RUN apt-get install -f -y python-dev python-pip
@@ -48,6 +49,10 @@ RUN pip2 install enum34
 RUN pip2 install thrift==0.13.0
 RUN pip3 install thrift==0.13.0
 
+# We install the libpci module in order to be able to do PCI transactions
+RUN pip2 install libpci
+RUN pip3 install libpci
+
 {% if docker_platform_monitor_debs.strip() -%}
 # Copy locally-built Debian package dependencies
 {{ copy_files("debs/", docker_platform_monitor_debs.split(' '), "/debs/") }}