These are a more scalable way to apply firmware across a variety of
platforms.
An example:
```
XPS 13 7390 TPM 2.0
DeviceId: c56e9f77cfee65151bdef90310776f9d62827f5a
Guid: a4352c96-f8d7-526c-8485-7f84085f348e <- 0962-2.0
Guid: 7d65b10b-bb24-552d-ade5-590b3b278188 <- DELL-TPM-2.0-NTC-NPCT
Guid: 6f5ddd3a-8339-5b2a-b9a6-cf3b92f6c86d <- DELL-TPM-2.0-NTC-NPCT75x
Guid: fe462d4a-e48f-5069-9172-47330fc5e838 <- DELL-TPM-2.0-NTC-NPCT75xrls
Summary: Platform TPM device
Plugin: uefi
Flags: internal|require-ac|registered
Vendor: Dell Inc.
Version: 7.2.1.0
VersionFormat: quad
Icon: computer
Created: 2019-09-04
```
When this system is queried using tpm2-tools:
```
$ sudo tpm2_getcap -c properties-fixed
TPM_PT_FAMILY_INDICATOR:
as UINT32: 0x08322e3000
as string: "2.0"
TPM_PT_LEVEL: 0
TPM_PT_REVISION: 1.38
TPM_PT_DAY_OF_YEAR: 0x00000008
TPM_PT_YEAR: 0x000007e2
TPM_PT_MANUFACTURER: 0x4e544300
TPM_PT_VENDOR_STRING_1:
as UINT32: 0x4e504354
as string: "NPCT"
TPM_PT_VENDOR_STRING_2:
as UINT32: 0x37357800
as string: "75x"
TPM_PT_VENDOR_STRING_3:
as UINT32: 0x02010024
as string: ""
TPM_PT_VENDOR_STRING_4:
as UINT32: 0x726c7300
as string: "rls"
```
This is a large commit that removes all the providers and turns them into
plugins. I think having both providers _and_ plugins was super confusing.
Plugins are loaded at runtime so you could in theory develop a new plugin
without putting it in the fwupd source tree, although there are no installed
headers or PC files as I'm not sure it's a good idea at this stage.
This commit moves all the per-provider docs, tests, notes, debug dumps and test
data to plugin-specific directories -- these also allows the plugin author to
"own" more of the source tree so we don't enforce fu- prefixes and the style
guide everywhere.
This allows us to run the same action on all the plugins in the future, so we
could have a prepare(FuPlugin, FuDevice) and cleanup(FuPlugin, FuDevice) run
on *all* plugins, so doing an update using one plugin would allow us to work
around hardware quirks in other plugins.
If I've broken your out-of-tree provider it's trivial to port to the new API
with sed and a fixed up build file. If you need help please let me know.
