README.md: Fix mark-down nested bullet syntax

Change-Id: I252fa946010a2750d268b604d72e070ada99931c
diff --git a/README.md b/README.md
index b7aef38..e222994 100644
--- a/README.md
+++ b/README.md
@@ -14,11 +14,11 @@
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 * Osmocom SIMtrace 1.x with SAM3 controller
-** this is open hardware and schematics / PCB design is published
+ * this is open hardware and schematics / PCB design is published
 * sysmocom sysmoQMOD (with 4 Modems,  4 SIM slots and 2 SAM3)
-** this is a proprietary device, publicly available from sysmocom
+ * this is a proprietary device, publicly available from sysmocom
 * sysmocom OWHW (with 2 Modems and 1 SAM3 onboard)
-** this is not publicly available hardware, but still supported
+ * this is not publicly available hardware, but still supported
 
 This Repository
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