make host-cryptopp selectable

Quoting Thomas Petazzoni, the current situation is:

* Most host packages don't have any Config.in.host options (blind or visible), because they are merely build dependencies of other packages.

* A few host packages do have a visible Config.in.host because they are useful by themselves, and not just as a build dependency of something else: image generation tools, flashing tools, qemu, etc.

The idea we have for the future is:

* All host packages have a Config.in.host option.

* The host packages that are only build dependencies of other packages have a blind Config.in.host option

* The host packages that are useful by themselves continue to have a visible Config.in.host option.

Carlos Santos (2):
package/cryptopp: add a blind Config.in.host
package/tegrarcm: select host-cryptopp

 package/Config.in.host          | 1 +
 package/cryptopp/Config.in.host | 6 ++++++
 package/tegrarcm/Config.in.host | 1 +
 3 files changed, 8 insertions(+)
 create mode 100644 package/cryptopp/Config.in.host

2.19.2

Quoting Thomas Petazzoni, the idea we have for the future is:

* All host packages have a Config.in.host option.

* The host packages that are only build dependencies of other packages have a blind Config.in.host option

* The host packages that are useful by themselves continue to have a visible Config.in.host option.

host-cryptopp gets a blind Config.in.host, since only exists to build tegrarcm. A help text is included to document the package, only, since it is not shown in the configuration menu.

---
Changes v1->v2:
- Explain the motivation in the commit message
- Make the Config.in.host blind

---
 package/Config.in.host          | 1 +
 package/cryptopp/Config.in.host | 6 ++++++
 2 files changed, 7 insertions(+)
 create mode 100644 package/cryptopp/Config.in.host

index 16b474fc9d..04537fc2e2 100644
@@ -9,6 +9,7 @@ menu "Host utilities"
 	source "package/checksec/Config.in.host"
 	source "package/cmake/Config.in.host"
 	source "package/cramfs/Config.in.host"
+	source "package/cryptopp/Config.in.host"
 	source "package/cryptsetup/Config.in.host"
 	source "package/dfu-util/Config.in.host"
 	source "package/dos2unix/Config.in.host"

new file mode 100644
index 0000000000..e8159b0a7e
@@ -0,0 +1,6 @@
+config BR2_PACKAGE_HOST_CRYPTOPP
+	bool
+	help
+	  A free C++ class library of cryptographic schemes
+
+	  https://www.cryptopp.com/

2.19.2

Since cryptopp now has a Config.in.host, make the depending packages (currently only tegrarcm) select it.

---
Changes v1->v2:
- Explain the motivation in the commit message
- Restore the BR2_arm dependency

---
 package/tegrarcm/Config.in.host | 1 +
 1 file changed, 1 insertion(+)

index d8cbb947d6..aeff8f158c 100644
@@ -1,6 +1,7 @@
 config BR2_PACKAGE_HOST_TEGRARCM
 	bool "host tegrarcm"
 	depends on BR2_arm || BR2_armeb
+	select BR2_PACKAGE_HOST_CRYPTOPP
 	help
 	  This program is used to send code to a Tegra device in
 	  recovery mode.

2.19.2