Corrected wrong order in subtraction for UDP available

[baender]

This is the pull request to issue #66
The calculation of available bytes in UDP.available() seems to be reverted. Changing the order in the subtraction leads to the correct number of bytes available.

[github-actions]

Memory usage change @ f7fcf36

Board	flash	%	RAM for global variables	%
arduino:samd:mkrnb1500	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/GPRSUdpNtpClient flash	%	examples/GPRSUdpNtpClient RAM for global variables	%	examples/NBSSLWebClient flash	%	examples/NBSSLWebClient RAM for global variables	%	examples/NBWebClient flash	%	examples/NBWebClient RAM for global variables	%	examples/ReceiveSMS flash	%	examples/ReceiveSMS RAM for global variables	%	examples/SendSMS flash	%	examples/SendSMS RAM for global variables	%	examples/Tools/ChooseRadioAccessTechnology flash	%	examples/Tools/ChooseRadioAccessTechnology RAM for global variables	%	examples/Tools/NBScanNetworks flash	%	examples/Tools/NBScanNetworks RAM for global variables	%	examples/Tools/PinManagement flash	%	examples/Tools/PinManagement RAM for global variables	%	examples/Tools/SerialSARAPassthrough flash	%	examples/Tools/SerialSARAPassthrough RAM for global variables	%	examples/Tools/TestGPRS flash	%	examples/Tools/TestGPRS RAM for global variables	%	examples/Tools/TestModem flash	%	examples/Tools/TestModem RAM for global variables	%
arduino:samd:mkrnb1500	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0

Click for full report CSV

Board,examples/GPRSUdpNtpClient<br>flash,%,examples/GPRSUdpNtpClient<br>RAM for global variables,%,examples/NBSSLWebClient<br>flash,%,examples/NBSSLWebClient<br>RAM for global variables,%,examples/NBWebClient<br>flash,%,examples/NBWebClient<br>RAM for global variables,%,examples/ReceiveSMS<br>flash,%,examples/ReceiveSMS<br>RAM for global variables,%,examples/SendSMS<br>flash,%,examples/SendSMS<br>RAM for global variables,%,examples/Tools/ChooseRadioAccessTechnology<br>flash,%,examples/Tools/ChooseRadioAccessTechnology<br>RAM for global variables,%,examples/Tools/NBScanNetworks<br>flash,%,examples/Tools/NBScanNetworks<br>RAM for global variables,%,examples/Tools/PinManagement<br>flash,%,examples/Tools/PinManagement<br>RAM for global variables,%,examples/Tools/SerialSARAPassthrough<br>flash,%,examples/Tools/SerialSARAPassthrough<br>RAM for global variables,%,examples/Tools/TestGPRS<br>flash,%,examples/Tools/TestGPRS<br>RAM for global variables,%,examples/Tools/TestModem<br>flash,%,examples/Tools/TestModem<br>RAM for global variables,%
arduino:samd:mkrnb1500,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0

[aentinger]

Excellent catch 👍 Thank you very much @baender 🚀

[aentinger]

This fixes #66.