QA:Testcase SwapOnZRAM customconfig

Description

Test enable swap-on-zram with a custom configuration.

How to test

1. swap-on-zram should be enabled and running to start this test.
2. Create a custom configuration file.

   $ sudo cp /usr/share/doc/zram-generator/zram-generator.conf.example /etc/systemd/zram-generator.conf
   $ sudo nano /etc/systemd/zram-generator.conf
   <li> Confirm you're getting the results you expect.
   <pre>
   $ sudo systemctl status swap-create@zram0
   ● swap-create@zram0.service - Create swap on /dev/zram0
        Loaded: loaded (/usr/lib/systemd/system/swap-create@.service; static; vendor preset: disabled)
        Active: active (exited) since Sun 2020-06-28 19:52:48 MDT; 1min 0s ago
          Docs: man:zram-generator(8)
                man:zram-generator.conf(5)
       Process: 650 ExecStart=/usr/lib/systemd/system-generators/zram-generator --setup-device zram0 (code=exited, status=0/SUCCESS)
      Main PID: 650 (code=exited, status=0/SUCCESS)
           CPU: 28ms
   
   Jun 28 19:52:48 fmac.local systemd[1]: Starting Create swap on /dev/zram0...
   Jun 28 19:52:48 fmac.local zram-generator[653]: Setting up swapspace version 1, size = 512 MiB (536866816 bytes)
   Jun 28 19:52:48 fmac.local zram-generator[653]: no label, UUID=72991b9c-f8fd-459c-9bb8-6e8ac19a16c2
   Jun 28 19:52:48 fmac.local systemd[1]: Finished Create swap on /dev/zram0.
   $ zramctl
   NAME       ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT
   /dev/zram0 lzo-rle       512M   4K   73B   12K       8 [SWAP]
   $ swapon
   NAME       TYPE       SIZE USED PRIO
   /dev/sda5  partition 10.4G   0B   -2
   /dev/zram0 partition  512M   0B  100
   $ 

Expected Results

1. Status should be active (exited).
2. There should be a /dev/zram0 device listed for the zramctl properly sized, with the compression algorithm you specified in the configuration file.
3. The /dev/zram0 device should appear for the swapon command, with the proper size and a priority of 100.