Fix realsense2 save and read examples + PCL defines usage

[fspindle]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 45.63%. Comparing base (4a5e001) to head (c9c2553).
Report is 45 commits behind head on master.

Files	Patch %	Lines
example/device/framegrabber/readRealSenseData.cpp	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1392   +/-   ##
=======================================
  Coverage   45.63%   45.63%           
=======================================
  Files        1069     1069           
  Lines      108115   108115           
  Branches    18713    18713           
=======================================
  Hits        49340    49340           
  Misses      58775    58775           

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