parsec: fix package name on README with underscore

Author: cirosantilli

README.adoc

@@ -9089,7 +9089,7 @@ Running a benchmark of a size different than `test`, e.g. `simsmall`, requires a
   --arch arm \
   --config 'BR2_PACKAGE_PARSEC_BENCHMARK=y' \
   --config 'BR2_PACKAGE_PARSEC_BENCHMARK_INPUT_SIZE="simsmall"' \
-  -- parsec-benchmark-reconfigure \
+  -- parsec_benchmark-reconfigure \
 ;
 ....
 
@@ -9147,7 +9147,7 @@ If you still want to run this, try it out with:
   --config 'BR2_PACKAGE_PARSEC_BENCHMARK=y' \
   --config 'BR2_PACKAGE_PARSEC_BENCHMARK_PARSECMGMT=y' \
   --config 'BR2_TARGET_ROOTFS_EXT2_SIZE="3G"' \
-  -- parsec-benchmark-reconfigure \
+  -- parsec_benchmark-reconfigure \
 ;
 ....
 
@@ -9201,7 +9201,7 @@ Don't forget to explicitly rebuild PARSEC with:
 ./build-buildroot \
   --arch arm \
   --config 'BR2_PACKAGE_PARSEC_BENCHMARK=y' \
-  -- parsec-benchmark-reconfigure \
+  -- parsec_benchmark-reconfigure \
 ;
 ....
 +