Align with ESP8266 and fix signature deviation between Arduino.h and WMath.cpp

[dok-net]

As per esp8266/Arduino#8089, newer compilers flag the different types in Arduino.h and WMath.cpp for makeWord as an error. Proactively fix this for ESP32.
A patch is provided in PR #5230

Edit: ESP32 master branch actually fails on this MCVE, too:

void setup()
{
    auto w = makeWord(1024);
    auto w2 = makeWord(192, 193);
}

void loop()
{
}

ld.exe: makeword.cpp.o:(.literal._Z5setupv+0x18): undefined reference to makeWord(unsigned short)

Error linking for board WEMOS D1 MINI ESP32
ld.exe: makeword.cpp.o: in function setup()
makeword.ino:3: undefined reference to makeWord(unsigned short)
Debug build failed for project 'makeword'
 
collect2.exe*: error: ld returned 1 exit status