Add additionals possible pinctrl group for pwm2~7 on pins
pin 4 (GPIO_A) pwm7
pin 58 (JTAG_JTDI) pwm2
pin 59 (JTAG_JTDO) pwm3
pin 60 (JTAG_JTMS) pwm4
pin 61 (JTAG_JTCLK) pwm5
pin 62 (JTAG_JTRST_N) pwm6
They can be useful e.g. on the BPi-R4 as in that way pwm2~6 can be exposed
on the 26-pin header (pwm6 always, pwm2~5 instead of the full UART).
Signed-off-by: Daniel Golle <daniel@makrotopia.org>