regulator: cpcap-regulator: Demote kerneldoc header to standard comment

Nothing about this comment identifies it as a kerneldoc header.
They're missing all of their struct's property descriptions and
the correct 'struct *' header.

Fixes the following W=1 warning(s):

 drivers/regulator/cpcap-regulator.c:99: warning: cannot understand function prototype: 'struct cpcap_regulator '
 drivers/regulator/cpcap-regulator.c:337: warning: cannot understand function prototype: 'const struct cpcap_regulator omap4_regulators[] = '
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200625163614.4001403-9-lee.jones@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/cpcap-regulator.c

@@ -89,7 +89,7 @@
  */
 #define CPCAP_REG_OFF_MODE_SEC		BIT(15)
 
-/**
+/*
  * SoC specific configuration for CPCAP regulator. There are at least three
  * different SoCs each with their own parameters: omap3, omap4 and tegra2.
  *
@@ -325,7 +325,7 @@ static const unsigned int vvib_val_tbl[] = { 1300000, 1800000, 2000000,
 static const unsigned int vusb_val_tbl[] = { 0, 3300000, };
 static const unsigned int vaudio_val_tbl[] = { 0, 2775000, };
 
-/**
+/*
  * SoC specific configuration for omap4. The data below is comes from Motorola
  * Linux kernel tree. It's basically the values of cpcap_regltr_data,
  * cpcap_regulator_mode_values and cpcap_regulator_off_mode_values, see