Fix rdcd crash on rocmtools fields read

- Solve issue that resulted in rdcd crash when reading registers 700-799
  by setting ROCMTOOLS_METRICS_PATH in rdc.service

README changes:
- Change default install path for gRPC
- Simplify install instructions
- Make more commands copy-pasteable
- Replace /opt/rocm-<version> with /opt/rocm
- Misc fixes

Change-Id: I39a2896ed2af5a3889f4b36cd8bcc8d3e9593585
Signed-off-by: Galantsev, Dmitrii <dmitrii.galantsev@amd.com>

server/rdc.service.in

@@ -18,6 +18,11 @@ Group=rdc
 
 Type=simple
 
+# Needed for accessing fields 700-799 provided by ROCMTools
+# At the time of writing - rdcd will crash if these metrics are accessed
+# without the following environment variable
+Environment=ROCMTOOLS_METRICS_PATH=/@CPACK_PACKAGING_INSTALL_PREFIX@/libexec/rocmtools/counters/derived_counters.xml
+
 CapabilityBoundingSet=CAP_DAC_OVERRIDE
 AmbientCapabilities=CAP_DAC_OVERRIDE