test: Add scenario file for each target and support single case running

Different test cases are needed for different targets. A folder "scenario"
is created under scripts/qemuimage-tests to hold scenario files for different
targets.

Single case running is supported now. User can run single case together with
a whole test suite by setting variable TEST_SCEN in local.conf.

By default test cases in sanity suite will be ran. If you want to run other
test suite or specific test case(e.g. bat or boot test case under sanity suite),
list them like following.
TEST_SCEN = "sanity bat sanity:boot"

Signed-off-by Jiajun Xu <jiajun.xu@intel.com>

scripts/qemuimage-tests/scenario/qemuarm/poky-image-minimal

@@ -0,0 +1 @@
+sanity boot

scripts/qemuimage-tests/scenario/qemuarm/poky-image-sato

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemuarm/poky-image-sdk

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemumips/poky-image-minimal

@@ -0,0 +1 @@
+sanity boot

scripts/qemuimage-tests/scenario/qemumips/poky-image-sato

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemumips/poky-image-sdk

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemuppc/poky-image-minimal

@@ -0,0 +1 @@
+sanity boot

scripts/qemuimage-tests/scenario/qemuppc/poky-image-sato

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemuppc/poky-image-sdk

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemux86/poky-image-minimal

@@ -0,0 +1 @@
+sanity boot

scripts/qemuimage-tests/scenario/qemux86/poky-image-sato

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh

scripts/qemuimage-tests/scenario/qemux86/poky-image-sdk

@@ -0,0 +1,2 @@
+sanity boot
+sanity ssh