boards: pic32-clicker: Fix UART RX pinmux register
boards: pic32-clicker: Fix UART RX pinmux register

U3RXREG is the RX buffer for UART3. U3RXR is the register for
controlling the input pin for UART3.

Signed-off-by: Francois Berder <0eabc3e9da54407da074ac08d4217d54f5b94915@imgtec.com>

gebart/RIOT,adjih/RIOT,lazytech-org/RIOT,jasonatran/RIOT,mfrey/RIOT,roberthartung/RIOT,neumodisch/RIOT,gautric/RIOT,neumodisch/RIOT,OTAkeys/RIOT,dkm/RIOT,smlng/RIOT,neiljay/RIOT,RIOT-OS/RIOT,jfischer-phytec-iot/RIOT,Josar/RIOT,avmelnikoff/RIOT,mfrey/RIOT,immesys/RiSyn,thomaseichinger/RIOT,authmillenon/RIOT,x3ro/RIOT,aeneby/RIOT,Josar/RIOT,LudwigOrtmann/RIOT,smlng/RIOT,adrianghc/RIOT,josephnoir/RIOT,Ell-i/RIOT,rfuentess/RIOT,BytesGalore/RIOT,adrianghc/RIOT,yogo1212/RIOT,jasonatran/RIOT,Ell-i/RIOT,A-Paul/RIOT,aeneby/RIOT,rfuentess/RIOT,cladmi/RIOT,dailab/RIOT,thomaseichinger/RIOT,mfrey/RIOT,josephnoir/RIOT,gautric/RIOT,kYc0o/RIOT,OTAkeys/RIOT,miri64/RIOT,josephnoir/RIOT,dailab/RIOT,authmillenon/RIOT,toonst/RIOT,Hyungsin/RIOT-OS,aeneby/RIOT,immesys/RiSyn,syin2/RIOT,mtausig/RIOT,neiljay/RIOT,OlegHahm/RIOT,dailab/RIOT,kbumsik/RIOT,syin2/RIOT,A-Paul/RIOT,plushvoxel/RIOT,BytesGalore/RIOT,kaspar030/RIOT,beurdouche/RIOT,rfuentess/RIOT,adjih/RIOT,beurdouche/RIOT,OlegHahm/RIOT,dailab/RIOT,neiljay/RIOT,jfischer-phytec-iot/RIOT,adrianghc/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,kerneltask/RIOT,toonst/RIOT,adjih/RIOT,RIOT-OS/RIOT,LudwigKnuepfer/RIOT,Josar/RIOT,RIOT-OS/RIOT,gebart/RIOT,kaleb-himes/RIOT,ks156/RIOT,kaleb-himes/RIOT,kbumsik/RIOT,immesys/RiSyn,RIOT-OS/RIOT,ant9000/RIOT,basilfx/RIOT,thomaseichinger/RIOT,hamilton-mote/RIOT-OS,basilfx/RIOT,aeneby/RIOT,yogo1212/RIOT,kaleb-himes/RIOT,mtausig/RIOT,ant9000/RIOT,josephnoir/RIOT,beurdouche/RIOT,hamilton-mote/RIOT-OS,biboc/RIOT,jfischer-phytec-iot/RIOT,LudwigKnuepfer/RIOT,hamilton-mote/RIOT-OS,adrianghc/RIOT,adrianghc/RIOT,cladmi/RIOT,lazytech-org/RIOT,roberthartung/RIOT,cladmi/RIOT,authmillenon/RIOT,kaleb-himes/RIOT,miri64/RIOT,aeneby/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,dailab/RIOT,kerneltask/RIOT,Hyungsin/RIOT-OS,OlegHahm/RIOT,kaleb-himes/RIOT,LudwigOrtmann/RIOT,beurdouche/RIOT,ant9000/RIOT,kYc0o/RIOT,kaspar030/RIOT,dkm/RIOT,yogo1212/RIOT,mtausig/RIOT,kerneltask/RIOT,jfischer-phytec-iot/RIOT,LudwigKnuepfer/RIOT,smlng/RIOT,LudwigKnuepfer/RIOT,BytesGalore/RIOT,OTAkeys/RIOT,lazytech-org/RIOT,yogo1212/RIOT,neumodisch/RIOT,BytesGalore/RIOT,jasonatran/RIOT,x3ro/RIOT,thomaseichinger/RIOT,jasonatran/RIOT,Ell-i/RIOT,x3ro/RIOT,gautric/RIOT,neumodisch/RIOT,basilfx/RIOT,LudwigKnuepfer/RIOT,plushvoxel/RIOT,syin2/RIOT,hamilton-mote/RIOT-OS,thomaseichinger/RIOT,beurdouche/RIOT,Hyungsin/RIOT-OS,jfischer-phytec-iot/RIOT,mtausig/RIOT,plushvoxel/RIOT,neumodisch/RIOT,kYc0o/RIOT,Josar/RIOT,hamilton-mote/RIOT-OS,kYc0o/RIOT,avmelnikoff/RIOT,basilfx/RIOT,avmelnikoff/RIOT,plushvoxel/RIOT,toonst/RIOT,immesys/RiSyn,biboc/RIOT,avmelnikoff/RIOT,kYc0o/RIOT,OTAkeys/RIOT,authmillenon/RIOT,LudwigOrtmann/RIOT,adjih/RIOT,A-Paul/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,yogo1212/RIOT,Hyungsin/RIOT-OS,miri64/RIOT,gebart/RIOT,ks156/RIOT,BytesGalore/RIOT,biboc/RIOT,Hyungsin/RIOT-OS,toonst/RIOT,biboc/RIOT,authmillenon/RIOT,ks156/RIOT,dkm/RIOT,kaspar030/RIOT,jasonatran/RIOT,gautric/RIOT,RIOT-OS/RIOT,roberthartung/RIOT,neiljay/RIOT,immesys/RiSyn,Ell-i/RIOT,dkm/RIOT,neumodisch/RIOT,A-Paul/RIOT,OTAkeys/RIOT,authmillenon/RIOT,yogo1212/RIOT,miri64/RIOT,ks156/RIOT,lazytech-org/RIOT,OlegHahm/RIOT,x3ro/RIOT,adjih/RIOT,basilfx/RIOT,Josar/RIOT,avmelnikoff/RIOT,mfrey/RIOT,ant9000/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,neiljay/RIOT,gebart/RIOT,A-Paul/RIOT,kbumsik/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,josephnoir/RIOT,kaspar030/RIOT,rfuentess/RIOT,biboc/RIOT,roberthartung/RIOT,cladmi/RIOT,smlng/RIOT,rfuentess/RIOT,kbumsik/RIOT,mtausig/RIOT,gebart/RIOT,x3ro/RIOT,dkm/RIOT,syin2/RIOT,LudwigOrtmann/RIOT,kaspar030/RIOT,toonst/RIOT,Ell-i/RIOT,OlegHahm/RIOT,kerneltask/RIOT,miri64/RIOT,kerneltask/RIOT,syin2/RIOT,gautric/RIOT,kbumsik/RIOT,smlng/RIOT,mfrey/RIOT,LudwigOrtmann/RIOT,LudwigOrtmann/RIOT,cladmi/RIOT,immesys/RiSyn,lazytech-org/RIOT,roberthartung/RIOT,ks156/RIOT,plushvoxel/RIOT,ant9000/RIOT